UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act File Number: 811-22336

Large-Cap Core Research Portfolio

(Exact Name of Registrant as Specified in Charter)

Two International Place, Boston, Massachusetts 02110
(Address of Principal Executive Offices)

Maureen A. Gemma
Two International Place, Boston, Massachusetts 02110
(Name and Address of Agent for Services)

(617) 482-8260

(Registrant’s Telephone Number)

December 31

Date of Fiscal Year End

June 30, 2011

Date of Reporting Period

Item 1. Reports to Stockholders

Large-Cap Core Research Portfolio

June 30, 2011

Portfolio of Investments (Unaudited)

Common Stocks — 98.1%
Security	Shares		Value
Aerospace & Defense — 5.9%
Boeing Co. (The)		14,829	$	1,096,308
General Dynamics Corp.		43,715		3,257,642
Lockheed Martin Corp.		30,649		2,481,649
Raytheon Co.		46,168		2,301,475
United Technologies Corp.		54,382		4,813,351
			$	13,950,425
Auto Components — 0.9%
Johnson Controls, Inc.		52,953	$	2,206,022
			$	2,206,022
Beverages — 2.5%
Anheuser-Busch InBev NV ADR		16,083	$	932,975
Coca-Cola Co. (The)		38,846		2,613,948
Dr Pepper Snapple Group, Inc.		25,325		1,061,877
PepsiCo, Inc.		16,575		1,167,377
			$	5,776,177
Biotechnology — 1.3%
Amgen, Inc.(1)		23,948	$	1,397,366
Celgene Corp.(1)		26,087		1,573,568
			$	2,970,934
Capital Markets — 1.8%
Ameriprise Financial, Inc.		15,039	$	867,449
Goldman Sachs Group, Inc.		11,809		1,571,660
Invesco, Ltd.		31,772		743,465
T. Rowe Price Group, Inc.		18,524		1,117,738
			$	4,300,312
Chemicals — 2.6%
Air Products and Chemicals, Inc.		13,180	$	1,259,744
BASF SE		17,039		1,670,185
Ecolab, Inc.		23,247		1,310,666
PPG Industries, Inc.		20,228		1,836,500
			$	6,077,095
Commercial Banks — 3.6%
Fifth Third Bancorp		79,803	$	1,017,488
KeyCorp		128,133		1,067,348
PNC Financial Services Group, Inc.		25,778		1,536,627
SunTrust Banks, Inc.		39,933		1,030,271
Wells Fargo & Co.		133,462		3,744,944
			$	8,396,678
Commercial Services & Supplies — 0.4%
Waste Connections, Inc.		30,368	$	963,577
			$	963,577
Communications Equipment — 3.8%
HTC Corp.		83,000	$	2,806,332
JDS Uniphase Corp.(1)		45,359		755,681
Juniper Networks, Inc.(1)		39,248		1,236,312
QUALCOMM, Inc.		57,680		3,275,647
Telefonaktiebolaget LM Ericsson ADR		63,009		906,069
			$	8,980,041
Computers & Peripherals — 5.6%
Apple, Inc.(1)		33,593	$	11,276,163
EMC Corp.(1)		68,064		1,875,163
			$	13,151,326
Construction & Engineering — 0.7%
Fluor Corp.		25,459	$	1,646,179
			$	1,646,179
Consumer Finance — 0.8%
American Express Co.		36,492	$	1,886,636
			$	1,886,636
Diversified Financial Services — 4.6%
Bank of America Corp.		96,959	$	1,062,671
Citigroup, Inc.(1)		91,825		3,823,593
JPMorgan Chase & Co.		112,397		4,601,533
Moody’s Corp.		35,793		1,372,661
			$	10,860,458
Diversified Telecommunication Services — 2.0%
AT&T, Inc.		69,136	$	2,171,562
Verizon Communications, Inc.		70,025		2,607,031
			$	4,778,593

See Notes to Financial Statements.

15

Large-Cap Core Research Portfolio

June 30, 2011

Portfolio of Investments (Unaudited) — continued

Security	Shares		Value
Electric Utilities — 1.5%
American Electric Power Co., Inc.		40,042	$	1,508,783
PPL Corp.		69,253		1,927,311
			$	3,436,094
Electrical Equipment — 0.4%
Emerson Electric Co.		15,023	$	845,044
			$	845,044
Energy Equipment & Services — 1.9%
Halliburton Co.		43,543	$	2,220,693
Schlumberger, Ltd.		24,815		2,144,016
			$	4,364,709
Food & Staples Retailing — 2.4%
Kroger Co. (The)		37,477	$	929,430
Wal-Mart Stores, Inc.		55,911		2,971,110
Walgreen Co.		39,829		1,691,139
			$	5,591,679
Food Products — 1.5%
Green Mountain Coffee Roasters, Inc.(1)		20,419	$	1,822,600
Mead Johnson Nutrition Co., Class A		15,593		1,053,307
Nestle SA ADR		11,200		698,656
			$	3,574,563
Health Care Equipment & Supplies — 1.1%
Covidien PLC		25,849	$	1,375,942
St. Jude Medical, Inc.		26,097		1,244,305
			$	2,620,247
Health Care Providers & Services — 2.3%
AmerisourceBergen Corp.		40,425	$	1,673,595
Fresenius Medical Care AG & Co. KGaA ADR		16,516		1,233,745
UnitedHealth Group, Inc.		49,414		2,548,774
			$	5,456,114
Hotels, Restaurants & Leisure — 1.8%
Carnival Corp.		23,241	$	874,559
Marriott International, Inc., Class A		23,983		851,156
McDonald’s Corp.		30,228		2,548,825
			$	4,274,540
Household Products — 1.6%
Church & Dwight Co., Inc.		25,449	$	1,031,702
Colgate-Palmolive Co.		17,736		1,550,304
Henkel AG & Co. KGaA ADR		21,619		1,240,282
			$	3,822,288
Industrial Conglomerates — 1.5%
3M Co.		14,282	$	1,354,648
General Electric Co.		114,763		2,164,430
			$	3,519,078
Insurance — 2.8%
ACE, Ltd.		10,644	$	700,588
Aflac, Inc.		28,506		1,330,660
Lincoln National Corp.		31,293		891,537
MetLife, Inc.		36,372		1,595,640
Prudential Financial, Inc.		20,683		1,315,232
XL Group PLC		28,864		634,431
			$	6,468,088
Internet & Catalog Retail — 1.1%
Amazon.com, Inc.(1)		8,742	$	1,787,652
Expedia, Inc.		30,366		880,310
			$	2,667,962
Internet Software & Services — 1.8%
Google, Inc., Class A(1)		6,691	$	3,388,189
Yahoo! Inc.(1)		48,632		731,425
			$	4,119,614
IT Services — 2.3%
Accenture PLC, Class A		33,707	$	2,036,577
International Business Machines Corp.		12,474		2,139,915
Visa, Inc., Class A		15,350		1,293,391
			$	5,469,883
Leisure Equipment & Products — 0.4%
Hasbro, Inc.		23,391	$	1,027,567
			$	1,027,567
Machinery — 1.9%
Danaher Corp.		33,714	$	1,786,505
Illinois Tool Works, Inc.		45,312		2,559,675
			$	4,346,180

See Notes to Financial Statements.

16

Large-Cap Core Research Portfolio

June 30, 2011

Portfolio of Investments (Unaudited) — continued

Security	Shares		Value
Media — 2.8%
Comcast Corp., Class A		108,173	$	2,741,104
Omnicom Group, Inc.		20,264		975,914
Walt Disney Co. (The)		71,529		2,792,492
			$	6,509,510
Metals & Mining — 1.4%
BHP Billiton, Ltd. ADR		7,060	$	668,088
Cliffs Natural Resources, Inc.		8,803		813,837
Freeport-McMoRan Copper & Gold, Inc.		29,412		1,555,895
United States Steel Corp.		7,639		351,700
			$	3,389,520
Multi-Utilities — 1.8%
PG&E Corp.		32,224	$	1,354,375
Public Service Enterprise Group, Inc.		31,418		1,025,483
Sempra Energy		35,532		1,878,932
			$	4,258,790
Multiline Retail — 0.7%
Macy’s, Inc.		55,949	$	1,635,949
			$	1,635,949
Oil, Gas & Consumable Fuels — 10.5%
Alpha Natural Resources, Inc.(1)		41,432	$	1,882,670
Apache Corp.		19,980		2,465,332
ConocoPhillips		75,086		5,645,716
Exxon Mobil Corp.		99,563		8,102,437
Hess Corp.		22,296		1,666,849
Occidental Petroleum Corp.		17,496		1,820,284
Peabody Energy Corp.		28,499		1,678,876
Southwestern Energy Co.(1)		33,518		1,437,252
			$	24,699,416
Personal Products — 0.5%
Estee Lauder Cos., Inc. (The), Class A		12,056	$	1,268,171
			$	1,268,171
Pharmaceuticals — 6.5%
Abbott Laboratories		19,905	$	1,047,401
Allergan, Inc.		19,498		1,623,208
Johnson & Johnson		73,272		4,874,053
Novartis AG ADR		13,073		798,891
Pfizer, Inc.		182,707		3,763,764
Sanofi SA ADR		16,251		652,803
Shire PLC ADR		13,104		1,234,528
Teva Pharmaceutical Industries, Ltd. ADR		25,503		1,229,755
			$	15,224,403
Professional Services — 0.5%
Manpower, Inc.		19,513	$	1,046,872
			$	1,046,872
Real Estate Investment Trusts (REITs) — 1.6%
AvalonBay Communities, Inc.		7,902	$	1,014,617
Boston Properties, Inc.		8,882		942,913
Equity Residential		14,344		860,640
Simon Property Group, Inc.		7,911		919,495
			$	3,737,665
Semiconductors & Semiconductor Equipment — 0.4%
NXP Semiconductors NV(1)		31,361	$	838,280
			$	838,280
Software — 3.4%
Activision Blizzard, Inc.		71,494	$	835,050
Microsoft Corp.		135,243		3,516,318
Oracle Corp.		112,591		3,705,370
			$	8,056,738
Specialty Retail — 1.4%
Abercrombie & Fitch Co., Class A		13,859	$	927,444
Home Depot, Inc.		42,469		1,538,227
TJX Companies, Inc. (The)		16,828		883,975
			$	3,349,646
Textiles, Apparel & Luxury Goods — 0.8%
NIKE, Inc., Class B		19,416	$	1,747,052
			$	1,747,052
Tobacco — 2.1%
Philip Morris International, Inc.		57,145	$	3,815,572
Reynolds American, Inc.		32,725		1,212,461
			$	5,028,033

See Notes to Financial Statements.

17

Large-Cap Core Research Portfolio

June 30, 2011

Portfolio of Investments (Unaudited) — continued

Security	Shares		Value
Wireless Telecommunication Services — 0.9%
American Tower Corp., Class A(1)		41,625	$	2,178,236
			$	2,178,236
Total Common Stocks
(identified cost $196,262,994)			$	230,516,384
Short-Term Investments — 1.9%
	Interest
Description	(000’s omitted)		Value
Eaton Vance Cash Reserves Fund, LLC, 0.11%(2)	$	4,470	$	4,470,223
Total Short-Term Investments
(identified cost $4,470,223)			$	4,470,223
Total Investments — 100.0%
(identified cost $200,733,217)			$	234,986,607
Other Assets, Less Liabilities — 0.0%(3)			$	8,570
Net Assets — 100.0%			$	234,995,177

The percentage shown for each investment category in the Portfolio of Investments is based on net assets.

ADR - American Depositary Receipt

(1)	Non-income producing security.
(2)	Affiliated investment company available to Eaton Vance portfolios and funds which invests in high quality, U.S. dollar denominated money market instruments. The rate shown is the annualized seven-day yield as of June 30, 2011.
(3)	Amount is less than 0.05%.

See Notes to Financial Statements.

18

Large-Cap Core Research Portfolio

June 30, 2011

Statement of Assets and Liabilities (Unaudited)

Assets	June 30, 2011
Unaffiliated investments, at value (identified cost, $196,262,994)	$	230,516,384
Affiliated investment, at value (identified cost, $4,470,223)		4,470,223
Dividends receivable		275,107
Interest receivable from affiliated investment		514
Receivable for investments sold		3,587,609
Tax reclaims receivable		42,903
Total assets	$	238,892,740
Liabilities
Payable for investments purchased	$	3,732,626
Payable to affiliates:
Investment adviser fee		122,898
Trustees’ fees		1,950
Accrued expenses		40,089
Total liabilities	$	3,897,563
Net Assets applicable to investors’ interest in Portfolio	$	234,995,177
Sources of Net Assets
Net proceeds from capital contributions and withdrawals	$	200,741,589
Net unrealized appreciation		34,253,588
Total	$	234,995,177

See Notes to Financial Statements.

19

Large-Cap Core Research Portfolio

June 30, 2011

Statement of Operations (Unaudited)

	Six Months Ended
Investment Income	June 30, 2011
Dividends (net of foreign taxes, $37,510)	$	2,197,817
Interest allocated from affiliated investment		1,465
Expenses allocated from affiliated investment		(156	)
Total investment income	$	2,199,126
Expenses
Investment adviser fee	$	748,595
Trustees’ fees and expenses		3,987
Custodian fee		58,903
Legal and accounting services		18,382
Miscellaneous		5,017
Total expenses	$	834,884
Deduct —
Reduction of custodian fee	$	5
Total expense reductions	$	5
Net expenses	$	834,879
Net investment income	$	1,364,247
Realized and Unrealized Gain (Loss)
Net realized gain (loss) —
Investment transactions	$	7,542,258
Investment transactions allocated from affiliated investment		27
Foreign currency transactions		(7,175	)
Net realized gain	$	7,535,110
Change in unrealized appreciation (depreciation) —
Investments	$	1,520,247
Foreign currency		(132	)
Net change in unrealized appreciation (depreciation)	$	1,520,115
Net realized and unrealized gain	$	9,055,225
Net increase in net assets from operations	$	10,419,472

See Notes to Financial Statements.

20

Large-Cap Core Research Portfolio

June 30, 2011

Statements of Changes in Net Assets

	Six Months Ended
	June 30, 2011			Year Ended
Increase (Decrease) in Net Assets	(Unaudited)			December 31, 2010
From operations —
Net investment income	$	1,364,247		$	2,313,065
Net realized gain (loss) from investment and foreign currency transactions		7,535,110			(2,185,317	)
Net change in unrealized appreciation (depreciation) from investments and foreign currency		1,520,115			21,701,835
Net increase in net assets from operations	$	10,419,472		$	21,829,583
Capital transactions —
Contributions	$	27,116,515		$	39,512,953
Withdrawals		(25,395,175	)		(52,640,746	)
Net increase (decrease) in net assets from capital transactions	$	1,721,340		$	(13,127,793	)
Net increase in net assets	$	12,140,812		$	8,701,790
Net Assets
At beginning of period	$	222,854,365		$	214,152,575
At end of period	$	234,995,177		$	222,854,365

See Notes to Financial Statements.

21

Large-Cap Core Research Portfolio

June 30, 2011

Supplementary Data

	Six Months Ended
	June 30, 2011			Year Ended			Period Ended
Ratios/Supplemental Data	(Unaudited)			December 31, 2010			December 31, 2009(1)
Ratios (as a percentage of average daily net assets):
Expenses(2)		0.72	%(3)		0.73	%		0.86	%(3)
Net investment income		1.18	%(3)		1.09	%		1.19	%(3)
Portfolio Turnover		30	%(4)		44	%		10	%(4)
Total Return		4.68	%(4)		10.68	%		8.63	%(4)
Net assets, end of period (000’s omitted)	$	234,995		$	222,854		$	214,153

(1)	For the period from the start of business, November 1, 2009, to December 31, 2009.
(2)	Excludes the effect of custody fee credits, if any, of less than 0.005%.
(3)	Annualized.
(4)	Not annualized.

See Notes to Financial Statements.

22

Large-Cap Core Research Portfolio

June 30, 2011

Notes to Financial Statements (Unaudited)

1 Significant Accounting Policies

Large-Cap Core Research Portfolio (the Portfolio) is a Massachusetts business trust registered under the Investment Company Act of 1940, as amended (the 1940 Act), as a diversified, open-end management investment company. The Portfolio’s investment objective is to achieve long-term capital appreciation by investing in a diversified portfolio of equity securities. The Declaration of Trust permits the Trustees to issue interests in the Portfolio. At June 30, 2011, Eaton Vance Large-Cap Core Research Fund and Eaton Vance Balanced Fund held an interest of 27.4% and 60.8%, respectively, in the Portfolio.

The following is a summary of significant accounting policies of the Portfolio. The policies are in conformity with accounting principles generally accepted in the United States of America.

A Investment Valuation — Equity securities (including common shares of closed-end investment companies) listed on a U.S. securities exchange generally are valued at the last sale or closing price on the day of valuation or, if no sales took place on such date, at the mean between the closing bid and asked prices therefore on the exchange where such securities are principally traded. Equity securities listed on the NASDAQ Global or Global Select Market generally are valued at the NASDAQ official closing price. Unlisted or listed securities for which closing sales prices or closing quotations are not available are valued at the mean between the latest available bid and asked prices or, in the case of preferred equity securities that are not listed or traded in the over-the-counter market, by a third party pricing service that will use various techniques that consider factors including, but not limited to, prices or yields of securities with similar characteristics, benchmark yields, broker/dealer quotes, quotes of underlying common stock, issuer spreads, as well as industry and economic events. Short-term debt obligations purchased with a remaining maturity of sixty days or less are generally valued at amortized cost, which approximates market value. Foreign securities and currencies are valued in U.S. dollars, based on foreign currency exchange rate quotations supplied by a third party pricing service. The pricing service uses a proprietary model to determine the exchange rate. Inputs to the model include reported trades and implied bid/ask spreads. The daily valuation of exchange-traded foreign securities generally is determined as of the close of trading on the principal exchange on which such securities trade. Events occurring after the close of trading on foreign exchanges may result in adjustments to the valuation of foreign securities to more accurately reflect their fair value as of the close of regular trading on the New York Stock Exchange. When valuing foreign equity securities that meet certain criteria, the Portfolio’s Trustees have approved the use of a fair value service that values such securities to reflect market trading that occurs after the close of the applicable foreign markets of comparable securities or other instruments that have a strong correlation to the fair-valued securities. Investments for which valuations or market quotations are not readily available or are deemed unreliable are valued at fair value using methods determined in good faith by or at the direction of the Trustees of the Portfolio in a manner that most fairly reflects the security’s value, or the amount that the Portfolio might reasonably expect to receive for the security upon its current sale in the ordinary course. Each such determination is based on a consideration of all relevant factors, which are likely to vary from one pricing context to another. These factors may include, but are not limited to, the type of security, the existence of any contractual restrictions on the security’s disposition, the price and extent of public trading in similar securities of the issuer or of comparable companies or entities, quotations or relevant information obtained from broker-dealers or other market participants, information obtained from the issuer, analysts, and/or the appropriate stock exchange (for exchange-traded securities), an analysis of the company’s or entity’s financial condition, and an evaluation of the forces that influence the issuer and the market(s) in which the security is purchased and sold.

The Portfolio may invest in Eaton Vance Cash Reserves Fund, LLC (Cash Reserves Fund), an affiliated investment company managed by Eaton Vance Management (EVM). Cash Reserves Fund generally values its investment securities utilizing the amortized cost valuation technique in accordance with Rule 2a-7 under the 1940 Act. This technique involves initially valuing a portfolio security at its cost and thereafter assuming a constant amortization to maturity of any discount or premium. If amortized cost is determined not to approximate fair value, Cash Reserves Fund may value its investment securities based on available market quotations provided by a third party pricing service.

B Investment Transactions — Investment transactions for financial statement purposes are accounted for on a trade date basis. Realized gains and losses on investments sold are determined on the basis of identified cost.

C Income — Dividend income is recorded on the ex-dividend date for dividends received in cash and/or securities. However, if the ex-dividend date has passed, certain dividends from foreign securities are recorded as the Portfolio is informed of the ex-dividend date. Withholding taxes on foreign dividends and capital gains have been provided for in accordance with the Portfolio’s understanding of the applicable countries’ tax rules and rates. Interest income is recorded on the basis of interest accrued, adjusted for amortization of premium or accretion of discount.

D Federal Taxes — The Portfolio has elected to be treated as a partnership for federal tax purposes. No provision is made by the Portfolio for federal or state taxes on any taxable income of the Portfolio because each investor in the Portfolio is ultimately responsible for the payment of any taxes on its share of taxable income. Since at least one of the Portfolio’s investors is a regulated investment company that invests all or substantially all of its assets in the Portfolio, the Portfolio normally must satisfy the applicable source of income and diversification requirements (under the Internal Revenue Code) in order for its investors to satisfy them. The Portfolio will allocate, at least annually among its investors, each investor’s distributive share of the Portfolio’s net investment income, net realized capital gains and any other items of income, gain, loss, deduction or credit.

As of June 30, 2011, the Portfolio had no uncertain tax positions that would require financial statement recognition, de-recognition, or disclosure. Each of the Portfolio’s federal tax returns filed since the start of business on November 1, 2009 to December 31, 2010 remains subject to examination by the Internal Revenue Service.

E Expense Reduction — State Street Bank and Trust Company (SSBT) serves as custodian of the Portfolio. Pursuant to the custodian agreement, SSBT receives a fee reduced by credits, which are determined based on the average daily cash balance the Portfolio maintains with SSBT. All credit balances, if any, used to reduce the Portfolio’s custodian fees are reported as a reduction of expenses in the Statement of Operations.

23

Large-Cap Core Research Portfolio

June 30, 2011

Notes to Financial Statements (Unaudited) — continued

F Foreign Currency Translation — Investment valuations, other assets, and liabilities initially expressed in foreign currencies are translated each business day into U.S. dollars based upon current exchange rates. Purchases and sales of foreign investment securities and income and expenses denominated in foreign currencies are translated into U.S. dollars based upon currency exchange rates in effect on the respective dates of such transactions. Recognized gains or losses on investment transactions attributable to changes in foreign currency exchange rates are recorded for financial statement purposes as net realized gains and losses on investments. That portion of unrealized gains and losses on investments that results from fluctuations in foreign currency exchange rates is not separately disclosed.

G Use of Estimates — The preparation of the financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of income and expense during the reporting period. Actual results could differ from those estimates.

H Indemnifications — Under the Portfolio’s organizational documents, its officers and Trustees may be indemnified against certain liabilities and expenses arising out of the performance of their duties to the Portfolio. Under Massachusetts law, if certain conditions prevail, interestholders in the Portfolio could be deemed to have personal liability for the obligations of the Portfolio. However, the Portfolio’s Declaration of Trust contains an express disclaimer of liability on the part of Portfolio interestholders and the By-laws provide that the Portfolio shall assume the defense on behalf of any Portfolio interestholder. Moreover, the By-laws also provide for indemnification out of Portfolio property of any interestholder held personally liable solely by reason of being or having been an interestholder for all loss or expense arising from such liability. Additionally, in the normal course of business, the Portfolio enters into agreements with service providers that may contain indemnification clauses. The Portfolio’s maximum exposure under these arrangements is unknown as this would involve future claims that may be made against the Portfolio that have not yet occurred.

I Interim Financial Statements — The interim financial statements relating to June 30, 2011 and for the six months then ended have not been audited by an independent registered public accounting firm, but in the opinion of the Portfolio’s management, reflect all adjustments, consisting only of normal recurring adjustments, necessary for the fair presentation of the financial statements.

2 Investment Adviser Fee and Other Transactions with Affiliates

The investment adviser fee is earned by Boston Management and Research (BMR), a subsidiary of EVM, as compensation for investment advisory services rendered to the Portfolio. The fee is computed at an annual rate of 0.65% of the Portfolio’s average daily net assets up to $500 million and at reduced rates on daily net assets of $500 million or more and is payable monthly. The Portfolio invests its cash in Cash Reserves Fund. EVM does not currently receive a fee for advisory services provided to Cash Reserves Fund. For the six months ended June 30, 2011, the Portfolio’s investment adviser fee amounted to $748,595.

Except for Trustees of the Portfolio who are not members of EVM’s or BMR’s organizations, officers and Trustees receive remuneration for their services to the Portfolio out of the investment adviser fee. Trustees of the Portfolio who are not affiliated with the investment adviser may elect to defer receipt of all or a percentage of their annual fees in accordance with the terms of the Trustees Deferred Compensation Plan. For the six months ended June 30, 2011, no significant amounts have been deferred. Certain officers and Trustees of the Portfolio are officers of the above organizations.

3 Purchases and Sales of Investments

Purchases and sales of investments, other than short-term obligations, aggregated $70,244,745 and $73,052,027, respectively, for the six months ended June 30, 2011.

4 Federal Income Tax Basis of Investments

The cost and unrealized appreciation (depreciation) of investments of the Portfolio at June 30, 2011, as determined on a federal income tax basis, were as follows:

Aggregate cost	$	200,757,649
Gross unrealized appreciation	$	37,350,229
Gross unrealized depreciation		(3,121,271	)
Net unrealized appreciation	$	34,228,958

5 Line of Credit

The Portfolio participates with other portfolios and funds managed by EVM and its affiliates in a $450 million unsecured line of credit agreement with a group of banks. Borrowings are made by the Portfolio solely to facilitate the handling of unusual and/or unanticipated short-term cash requirements.

24

Large-Cap Core Research Portfolio

June 30, 2011

Notes to Financial Statements (Unaudited) — continued

Interest is charged to the Portfolio based on its borrowings at an amount above either the Eurodollar rate or Federal Funds rate. In addition, a fee computed at an annual rate of 0.10% on the daily unused portion of the line of credit is allocated among the participating portfolios and funds at the end of each quarter. Because the line of credit is not available exclusively to the Portfolio, it may be unable to borrow some or all of its requested amounts at any particular time. The Portfolio did not have any significant borrowings or allocated fees during the six months ended June 30, 2011.

6 Risks Associated with Foreign Investments

Investing in securities issued by companies whose principal business activities are outside the United States may involve significant risks not present in domestic investments. For example, there is generally less publicly available information about foreign companies, particularly those not subject to the disclosure and reporting requirements of the U.S. securities laws. Certain foreign issuers are generally not bound by uniform accounting, auditing, and financial reporting requirements and standards of practice comparable to those applicable to domestic issuers. Investments in foreign securities also involve the risk of possible adverse changes in investment or exchange control regulations, expropriation or confiscatory taxation, limitation on the removal of funds or other assets of the Portfolio, political or financial instability or diplomatic and other developments which could affect such investments. Foreign securities markets, while growing in volume and sophistication, are generally not as developed as those in the United States, and securities of some foreign issuers (particularly those located in developing countries) may be less liquid and more volatile than securities of comparable U.S. companies. In general, there is less overall governmental supervision and regulation of foreign securities markets, broker-dealers and issuers than in the United States.

7 Fair Value Measurements

Under generally accepted accounting principles for fair value measurements, a three-tier hierarchy to prioritize the assumptions, referred to as inputs, is used in valuation techniques to measure fair value. The three-tier hierarchy of inputs is summarized in the three broad levels listed below.

•  Level 1 – quoted prices in active markets for identical investments

•  Level 2 – other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.)

•  Level 3 – significant unobservable inputs (including a fund’s own assumptions in determining the fair value of investments)

In cases where the inputs used to measure fair value fall in different levels of the fair value hierarchy, the level disclosed is determined based on the lowest level input that is significant to the fair value measurement in its entirety. The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

At June 30, 2011, the hierarchy of inputs used in valuing the Portfolio’s investments, which are carried at value, were as follows:

Asset Description	Level 1		Level 2			Level 3		Total
Common Stocks
Consumer Discretionary	$	23,418,248	$	—		$	—	$	23,418,248
Consumer Staples		25,060,911		—			—		25,060,911
Energy		29,064,125		—			—		29,064,125
Financials		35,649,837		—			—		35,649,837
Health Care		26,271,698		—			—		26,271,698
Industrials		26,317,355		—			—		26,317,355
Information Technology		37,809,550		2,806,332			—		40,615,882
Materials		7,796,430		1,670,185			—		9,466,615
Telecommunication Services		6,956,829		—			—		6,956,829
Utilities		7,694,884		—			—		7,694,884
Total Common Stocks	$	226,039,867	$	4,476,517	*	$	—	$	230,516,384
Short-Term Investments	$	—	$	4,470,223		$	—	$	4,470,223
Total Investments	$	226,039,867	$	8,946,740		$	—	$	234,986,607

* Includes foreign equity securities whose values were adjusted to reflect market trading of comparable securities or other correlated instruments that occurred after the close of trading in their applicable foreign markets.

The Portfolio held no investments or other financial instruments as of December 31, 2010 whose fair value was determined using Level 3 inputs. At June 30, 2011, the value of investments transferred between Level 1 and Level 2, if any, during the six months then ended was not significant.

25

Eaton Vance

Large-Cap Core Research Fund

June 30, 2011

Board of Trustees’ Contract Approval

Overview of the Contract Review Process

The Investment Company Act of 1940, as amended (the “1940 Act”), provides, in substance, that each investment advisory agreement between a fund and its investment adviser will continue in effect from year to year only if its continuance is approved at least annually by the fund’s board of trustees, including by a vote of a majority of the trustees who are not “interested persons” of the fund (“Independent Trustees”), cast in person at a meeting called for the purpose of considering such approval.

At a meeting of the Boards of Trustees (each a “Board”) of the Eaton Vance group of mutual funds (the “Eaton Vance Funds”) held on April 25, 2011, the Board, including a majority of the Independent Trustees, voted to approve continuation of existing advisory and sub-advisory agreements for the Eaton Vance Funds for an additional one-year period. In voting its approval, the Board relied upon the affirmative recommendation of the Contract Review Committee of the Board, which is a committee comprised exclusively of Independent Trustees. Prior to making its recommendation, the Contract Review Committee reviewed information furnished for a series of meetings of the Contract Review Committee held between February and April 2011. Such information included, among other things, the following:

Information about Fees, Performance and Expenses

•  An independent report comparing the advisory and related fees paid by each fund with fees paid by comparable funds;

•  An independent report comparing each fund’s total expense ratio and its components to comparable funds;

•  An independent report comparing the investment performance of each fund (including yield data and Sharpe and information ratios where relevant) to the investment performance of comparable funds over various time periods;

•  Data regarding investment performance in comparison to relevant peer groups of similarly managed funds and appropriate indices;

•  For each fund, comparative information concerning the fees charged and the services provided by each adviser in managing other mutual funds and institutional accounts using investment strategies and techniques similar to those used in managing such fund;

•  Profitability analyses for each adviser with respect to each fund;

Information about Portfolio Management

•  Descriptions of the investment management services provided to each fund, including the investment strategies and processes employed, and any changes in portfolio management processes and personnel;

•  Information about the allocation of brokerage and the benefits received by each adviser as a result of brokerage allocation, including information concerning the acquisition of research through client commission arrangements and/or the fund’s policies with respect to “soft dollar” arrangements;

•  Data relating to portfolio turnover rates of each fund;

•  The procedures and processes used to determine the fair value of fund assets and actions taken to monitor and test the effectiveness of such procedures and processes;

Information about each Adviser

•  Reports detailing the financial results and condition of each adviser;

•  Descriptions of the qualifications, education and experience of the individual investment professionals whose responsibilities include portfolio management and investment research for the funds, and information relating to their compensation and responsibilities with respect to managing other mutual funds and investment accounts;

•  Copies of the Codes of Ethics of each adviser and its affiliates, together with information relating to compliance with and the administration of such codes;

•  Copies of or descriptions of each adviser’s policies and procedures relating to proxy voting, the handling of corporate actions and class actions;

•  Information concerning the resources devoted to compliance efforts undertaken by each adviser and its affiliates on behalf of the funds (including descriptions of various compliance programs) and their record of compliance with investment policies and restrictions, including policies with respect to market-timing, late trading and selective portfolio disclosure, and with policies on personal securities transactions;

•  Descriptions of the business continuity and disaster recovery plans of each adviser and its affiliates;

•  A description of Eaton Vance Management’s procedures for overseeing third party advisers and sub-advisers;

Other Relevant Information

•  Information concerning the nature, cost and character of the administrative and other non-investment management services provided by Eaton Vance Management and its affiliates;

•  Information concerning management of the relationship with the custodian, subcustodians and fund accountants by each adviser or the funds’ administrator; and

•  The terms of each advisory agreement.

In addition to the information identified above, the Contract Review Committee considered information provided from time to time by each adviser throughout the year at meetings of the Board and its committees. Over the course of the twelve-month period ended April 30, 2011, with respect to one

26

Eaton Vance

Large-Cap Core Research Fund

June 30, 2011

Board of Trustees’ Contract Approval — continued

or more funds, the Board met nine times and the Contract Review Committee, the Audit Committee, the Governance Committee, the Portfolio Management Committee and the Compliance Reports and Regulatory Matters Committee, each of which is a Committee comprised solely of Independent Trustees, met nine, fifteen, seven, eight and twelve times, respectively. At such meetings, the Trustees received, among other things, presentations by the portfolio managers and other investment professionals of each adviser relating to the investment performance of each fund and the investment strategies used in pursuing the fund’s investment objective including, where relevant, the use of derivative instruments, as well as trading policies and procedures and risk management techniques.

For funds that invest through one or more underlying portfolios, the Board considered similar information about the portfolio(s) when considering the approval of advisory agreements. In addition, in cases where the fund’s investment adviser has engaged a sub-adviser, the Board considered similar information about the sub-adviser when considering the approval of any sub-advisory agreement.

The Contract Review Committee was assisted throughout the contract review process by Goodwin Procter LLP, legal counsel for the Independent Trustees. The members of the Contract Review Committee relied upon the advice of such counsel and their own business judgment in determining the material factors to be considered in evaluating each advisory and sub-advisory agreement and the weight to be given to each such factor. The conclusions reached with respect to each advisory and sub-advisory agreement were based on a comprehensive evaluation of all the information provided and not any single factor. Moreover, each member of the Contract Review Committee may have placed varying emphasis on particular factors in reaching conclusions with respect to each advisory and sub-advisory agreement.

Results of the Process

Based on its consideration of the foregoing, and such other information as it deemed relevant, including the factors and conclusions described below, the Contract Review Committee concluded that the continuance of the investment advisory agreement of Large-Cap Core Research Portfolio (the “Portfolio”), the portfolio in which Eaton Vance Large-Cap Core Research Fund (the “Fund”) invests, with Boston Management and Research (the “Adviser”), including its fee structure, is in the interests of shareholders and, therefore, the Contract Review Committee recommended to the Board approval of the agreement. The Board accepted the recommendation of the Contract Review Committee as well as the factors considered and conclusions reached by the Contract Review Committee with respect to the agreement. Accordingly, the Board, including a majority of the Independent Trustees, voted to approve continuation of the investment advisory agreement for the Portfolio.

Nature, Extent and Quality of Services

In considering whether to approve the investment advisory agreement of the Portfolio, the Board evaluated the nature, extent and quality of services provided to the Portfolio by the Adviser.

The Board considered the Adviser’s management capabilities and investment process with respect to the types of investments held by the Portfolio, including the education, experience and number of its investment professionals and other personnel who provide portfolio management, investment research, and similar services to the Portfolio. In particular, the Board evaluated, where relevant, the abilities and experience of such investment personnel in analyzing factors such as credit risk, tax efficiency, and special considerations relevant to investing in foreign markets. The Board also considered the Adviser’s in-house equity research capabilities. The Board also took into account the resources dedicated to portfolio management and other services, including the compensation methods of the Adviser to recruit and retain investment personnel, and the time and attention devoted to the Portfolio by senior management.

The Board also reviewed the compliance programs of the Adviser and relevant affiliates thereof. Among other matters, the Board considered compliance and reporting matters relating to personal trading by investment personnel, selective disclosure of portfolio holdings, late trading, frequent trading, portfolio valuation, business continuity and the allocation of investment opportunities. The Board also evaluated the responses of the Adviser and its affiliates to requests in recent years from regulatory authorities such as the Securities and Exchange Commission and the Financial Industry Regulatory Authority.

The Board considered shareholder and other administrative services provided or managed by Eaton Vance Management and its affiliates, including transfer agency and accounting services. The Board evaluated the benefits to shareholders of investing in a fund that is a part of a large family of funds, including the ability, in many cases, to exchange an investment among different funds without incurring additional sales charges.

After consideration of the foregoing factors, among others, the Board concluded that the nature, extent and quality of services provided by the Adviser, taken as a whole, are appropriate and consistent with the terms of the investment advisory agreement.

Fund Performance

The Board compared the Fund’s investment performance to a relevant universe of similarly managed funds identified by an independent data provider and appropriate benchmark indices. The Board reviewed comparative performance data for the one-, three- and five-year periods ended September 30, 2010 for the Fund. The Board concluded that the performance of the Fund was satisfactory.

27

Eaton Vance

Large-Cap Core Research Fund

June 30, 2011

Board of Trustees’ Contract Approval — continued

Management Fees and Expenses

The Board reviewed contractual investment advisory fee rates, including administrative fee rates payable by the Portfolio and by the Fund (referred to collectively as “management fees”). As part of its review, the Board considered the management fees and the Fund’s total expense ratio for the year ended September 30, 2010, as compared to a group of similarly managed funds selected by an independent data provider. The Board also considered factors that had an impact on Fund expense ratios, as identified by management in response to inquiries from the Contract Review Committee, as well as actions being taken to reduce expenses at the Eaton Vance fund complex level, including the negotiation of reduced fees for transfer agency and custody services. The Board considered the fact that the Adviser had waived fees and/or paid expenses for the Fund.

After reviewing the foregoing information, and in light of the nature, extent and quality of the services provided by the Adviser, the Board concluded that the management fees charged for advisory and related services are reasonable.

Profitability

The Board reviewed the level of profits realized by the Adviser and relevant affiliates thereof in providing investment advisory and administrative services to the Fund, to the Portfolio and to all Eaton Vance Funds as a group. The Board considered the level of profits realized without regard to revenue sharing or other payments by the Adviser and its affiliates to third parties in respect of distribution services. The Board also considered other direct or indirect benefits received by the Adviser and its affiliates in connection with its relationship with the Fund and the Portfolio, including the benefits of research services that may be available to the Adviser as a result of securities transactions effected for the Portfolio and other investment advisory clients.

The Board concluded that, in light of the foregoing factors and the nature, extent and quality of the services rendered, the profits realized by the Adviser and its affiliates are reasonable.

Economies of Scale

In reviewing management fees and profitability, the Board also considered the extent to which the Adviser and its affiliates, on the one hand, and the Fund and the Portfolio, on the other hand, can expect to realize benefits from economies of scale as the assets of the Fund and the Portfolio increase. The Board acknowledged the difficulty in accurately measuring the benefits resulting from the economies of scale with respect to the management of any specific fund or group of funds. The Board reviewed data summarizing the increases and decreases in the assets of the Fund and of all Eaton Vance Funds as a group over various time periods, and evaluated the extent to which the total expense ratio of the Fund and the profitability of the Adviser and its affiliates may have been affected by such increases or decreases. Based upon the foregoing, the Board concluded that the Fund currently shares in the benefits from economies of scale. The Board also concluded that, assuming reasonably foreseeable increases in the assets of the Portfolio, the structure of the advisory fee, which includes breakpoints at several asset levels, will allow the Fund to continue to benefit from economies of scale in the future.

28

Large-Cap Core Research Fund

June 30, 2011

Officers and Trustees

Officers of Eaton Vance Large-Cap Core Research Fund
Duncan W. Richardson President Payson F. Swaffield Vice President Barbara E. Campbell Treasurer	Maureen A. Gemma Vice President, Secretary and Chief Legal Officer Paul M. O’Neil Chief Compliance Officer

Officers of Large-Cap Core Research Portfolio
Charles B. Gaffney President Duncan W. Richardson Vice President Barbara E. Campbell Treasurer	Maureen A. Gemma Vice President, Secretary and Chief Legal Officer Paul M. O’Neil Chief Compliance Officer

Trustees of Eaton Vance Large-Cap Core Research Fund and Large-Cap Core Research Portfolio
Ralph F. Verni Chairman Benjamin C. Esty Thomas E. Faust Jr.* Allen R. Freedman	William H. Park Ronald A. Pearlman Helen Frame Peters Lynn A. Stout

* Interested Trustee

29

Eaton Vance

Large-Cap Core Research Fund

June 30, 2011

IMPORTANT NOTICES

Privacy. The Eaton Vance organization is committed to ensuring your financial privacy. Each of the financial institutions identified below has in effect the following policy (“Privacy Policy”) with respect to nonpublic personal information about its customers:

•  Only such information received from you, through application forms or otherwise, and information about your Eaton Vance fund transactions will be collected. This may include information such as name, address, social security number, tax status, account balances and transactions.

•  None of such information about you (or former customers) will be disclosed to anyone, except as permitted by law (which includes disclosure to employees necessary to service your account). In the normal course of servicing a customer’s account, Eaton Vance may share information with unaffiliated third parties that perform various required services such as transfer agents, custodians and broker/dealers.

•  Policies and procedures (including physical, electronic and procedural safeguards) are in place that are designed to protect the confidentiality of such information.

•  We reserve the right to change our Privacy Policy at any time upon proper notification to you. Customers may want to review our Privacy Policy periodically for changes by accessing the link on our homepage: www.eatonvance.com.

Our pledge of privacy applies to the following entities within the Eaton Vance organization: the Eaton Vance Family of Funds, Eaton Vance Management, Eaton Vance Investment Counsel, Eaton Vance Distributors, Inc., Eaton Vance Trust Company, Eaton Vance Management’s Real Estate Investment Group and Boston Management Research. In addition, our Privacy Policy applies only to those Eaton Vance customers who are individuals and who have a direct relationship with us. If a customer’s account (i.e., fund shares) is held in the name of a third-party financial advisor/broker-dealer, it is likely that only such advisor’s privacy policies apply to the customer. This notice supersedes all previously issued privacy disclosures. For more information about Eaton Vance’s Privacy Policy, please call 1-800-262-1122.

Delivery of Shareholder Documents. The Securities and Exchange Commission (SEC) permits funds to deliver only one copy of shareholder documents, including prospectuses, proxy statements and shareholder reports, to fund investors with multiple accounts at the same residential or post office box address. This practice is often called “householding” and it helps eliminate duplicate mailings to shareholders. Eaton Vance, or your financial advisor, may household the mailing of your documents indefinitely unless you instruct Eaton Vance, or your financial advisor, otherwise. If you would prefer that your Eaton Vance documents not be householded, please contact Eaton Vance at 1-800-262-1122, or contact your financial advisor. Your instructions that householding not apply to delivery of your Eaton Vance documents will be effective within 30 days of receipt by Eaton Vance or your financial advisor.

Portfolio Holdings. Each Eaton Vance Fund and its underlying Portfolio(s) (if applicable) will file a schedule of portfolio holdings on Form N-Q with the SEC for the first and third quarters of each fiscal year. The Form N-Q will be available on the Eaton Vance website at www.eatonvance.com, by calling Eaton Vance at 1-800-262-1122 or in the EDGAR database on the SEC’s website at www.sec.gov. Form N-Q may also be reviewed and copied at the SEC’s public reference room in Washington, D.C. (call 1-800-732-0330 for information on the operation of the public reference room).

Proxy Voting. From time to time, funds are required to vote proxies related to the securities held by the funds. The Eaton Vance Funds or their underlying Portfolios (if applicable) vote proxies according to a set of policies and procedures approved by the Funds’ and Portfolios’ Boards. You may obtain a description of these policies and procedures and information on how the Funds or Portfolios voted proxies relating to portfolio securities during the most recent 12-month period ended June 30, without charge, upon request, by calling 1-800-262-1122 and by accessing the SEC’s website at www.sec.gov.

30

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Investment Adviser of Large-Cap Core Research Portfolio
Boston Management and Research

Two International Place

Boston, MA 02110

Administrator of Eaton Vance Large-Cap Core Research Fund
Eaton Vance Management

Two International Place

Boston, MA 02110

Principal Underwriter*
Eaton Vance Distributors, Inc.

Two International Place

Boston, MA 02110

(617) 482-8260

Custodian
State Street Bank and Trust Company

200 Clarendon Street

Boston, MA 02116

Transfer Agent
BNY Mellon Investment Servicing (US) Inc.

Attn: Eaton Vance Funds

P.O. Box 9653

Providence, RI 02940-9653

(800) 262-1122

Fund Offices
Two International Place

Boston, MA 02110

*  FINRA BrokerCheck. Investors may check the background of their Investment Professional by contacting the Financial Industry Regulatory Authority (FINRA). FINRA BrokerCheck is a free tool to help investors check the professional background of current and former FINRA-registered securities firms and brokers. FINRA BrokerCheck is available by calling 1-800-289-9999 and at www.FINRA.org. The FINRA BrokerCheck brochure describing this program is available to investors at www.FINRA.org.

1325-8/11 ERSRC

Item 2. Code of Ethics

The registrant has adopted a code of ethics applicable to its Principal Executive Officer, Principal Financial Officer and Principal Accounting Officer. The registrant undertakes to provide a copy of such code of ethics to any person upon request, without charge, by calling 1-800-262-1122.

Item 3. Audit Committee Financial Expert

The registrant’s Board has designated William H. Park, an independent trustee, as its audit committee financial expert. Mr. Park is a certified public accountant who is the Chief Financial Officer of Aveon Group, L.P. (an investment management firm). Previously, he served as the Vice Chairman of Commercial Industrial Finance Corp. (specialty finance company), as President and Chief Executive Officer of Prizm Capital Management, LLC (investment management firm), as Executive Vice President and Chief Financial Officer of United Asset Management Corporation (an institutional investment management firm) and as a Senior Manager at Price Waterhouse (now PricewaterhouseCoopers) (an independent registered public accounting firm).

Item 4. Principal Accountant Fees and Services

Not required in this filing.

Item 5. Audit Committee of Listed Registrants

Not required in this filing.

Item 6. Schedule of Investments

Please see schedule of investments contained in the Report to Stockholders included under Item 1 of this Form N-CSR.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders

No Material Changes.

Item 11. Controls and Procedures

(a) It is the conclusion of the registrant’s principal executive officer and principal financial officer that the effectiveness of the registrant’s current disclosure controls and procedures (such disclosure controls and procedures having been evaluated within 90 days of the date of this filing) provide reasonable assurance that the information required to be disclosed by the registrant has been recorded, processed, summarized and reported within the time period specified in the Commission’s rules and forms and that the information required to be disclosed by the registrant has been accumulated and communicated to the registrant’s principal executive officer and principal financial officer in order to allow timely decisions regarding required disclosure.

(b) There have been no changes in the registrant’s internal controls over financial reporting during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Exhibits

(a)(1)	Registrant’s Code of Ethics — Not applicable (please see Item 2).
(a)(2)(i)	Treasurer’s Section 302 certification.
(a)(2)(ii)	President’s Section 302 certification.
(b)	Combined Section 906 certification.

Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Large-Cap Core Research Portfolio

By:	/s/ Charles B. Gaffney
	Charles B. Gaffney
	President

Date: August 16, 2011

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/ Barbara E. Campbell
	Barbara E. Campbell
	Treasurer

Date: August 16, 2011

By:	/s/ Charles B. Gaffney
	Charles B. Gaffney
	President

Date: August 16, 2011