UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED
MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number: (811-02608)

Exact name of registrant as specified in charter: Putnam Money Market Fund

Address of principal executive offices: One Post Office Square, Boston, Massachusetts 02109

Name and address of agent for service: Robert T. Burns, Vice President
One Post Office Square
Boston, Massachusetts 02109

Copy to:         Bryan Chegwidden, Esq.
Ropes & Gray LLP
1211 Avenue of the Americas
New York, New York 10036

Registrant's telephone number, including area code: (617) 292-1000

Date of fiscal year end: September 30, 2017

Date of reporting period: June 30, 2017

Item 1. Schedule of Investments:

Putnam Money Market Fund
The fund's portfolio
6/30/17 (Unaudited)
REPURCHASE AGREEMENTS (29.4%)(a)
			Principal amount	Value
Interest in $177,000,000 joint tri-party term repurchase agreement dated 6/29/17 with Citigroup Global Markets, Inc. due 7/6/17 - maturity value of $17,003,570 for an effective yield of 1.080% (collateralized by various mortgage backed securities and a U.S. Treasury bond with coupon rates ranging from 2.000% to 8.500% and due dates ranging from 12/1/18 to 6/1/51, valued at $180,540,000)			$17,000,000	$17,000,000
Interest in $188,865,000 joint tri-party repurchase agreement dated 6/30/17 with Citigroup Global Markets, Inc. due 7/3/17 - maturity value of $76,006,903 for an effective yield of 1.090% (collateralized by various mortgage backed securities and U.S. Treasury notes with coupon rates ranging from 1.250% to 9.000% and due dates ranging from 5/31/18 to 4/1/47, valued at $192,642,300)			76,000,000	76,000,000
Interest in $76,000,000 tri-party repurchase agreement dated 6/30/17 with Goldman, Sachs & Co. due 7/3/17 - maturity value of $76,006,777 for an effective yield of 1.070% (collateralized by various mortgage backed securities with coupon rates ranging from 3.000% to 4.000% and due dates ranging from 9/1/28 to 8/1/44, valued at $77,520,000)			76,000,000	76,000,000
Interest in $237,209,000 joint tri-party repurchase agreement dated 6/30/17 with Merrill Lynch, Pierce, Fenner & Smith, Inc. due 7/3/17 - maturity value of $75,078,819 for an effective yield of 1.090% (collateralized by various mortgage backed securities with coupon rates ranging from 2.500% to 3.500% and due dates ranging from 2/1/30 to 5/20/47, valued at $241,953,181)			75,072,000	75,072,000
Total repurchase agreements (cost $244,072,000)				$244,072,000
CERTIFICATES OF DEPOSIT (27.6%)(a)
	Yield (%)	Maturity date	Principal amount	Value
Bank of America, NA FRN	1.151	8/2/17	$5,500,000	$5,501,509
Bank of America, NA FRN	1.011	9/5/17	13,250,000	13,250,000
Bank of Montreal/Chicago, IL FRN (Canada)	1.367	10/3/17	9,000,000	9,000,000
Bank of Montreal/Chicago, IL FRN (Canada)	1.339	10/17/17	4,500,000	4,500,000
Bank of Nova Scotia/Houston FRN	1.534	9/7/17	8,500,000	8,500,000
BNP Paribas SA/New York, NY (France)	1.300	10/20/17	4,150,000	4,150,000
Canadian Imperial Bank of Commerce/New York, NY FRN	1.717	2/2/18	8,500,000	8,500,000
Canadian Imperial Bank of Commerce/New York, NY FRN	1.680	8/16/17	1,800,000	1,800,889
Citibank, NA	1.260	8/21/17	9,000,000	9,000,000
Citibank, NA	1.070	7/7/17	1,750,000	1,750,025
Citibank, NA	1.042	7/21/17	5,250,000	5,250,605
Commonwealth Bank of Australia 144A FRN (Australia)	1.174	5/2/18	4,000,000	4,000,000
Cooperatieve Rabobank UA/NY (Netherlands)	1.250	9/20/17	9,000,000	9,002,842
Cooperatieve Rabobank UA/NY FRN (Netherlands)	1.698	9/11/17	4,250,000	4,253,609
Credit Suisse AG/New York, NY	1.211	8/4/17	4,162,000	4,163,459
DNB Bank ASA/New York (Norway)	1.160	7/3/17	8,000,000	8,000,000
DNB Bank ASA/New York (Norway)	1.080	7/24/17	3,750,000	3,750,303
Mitsubishi UFJ Trust & Banking Corp./NY	1.200	8/23/17	4,000,000	4,001,862
Mizuho Bank, Ltd./NY FRN	1.737	7/13/17	8,250,000	8,251,476
Nordea Bank AB/New York, NY FRN	1.723	9/6/17	1,876,000	1,877,501
Nordea Bank Finland PLC/New York	1.262	7/5/17	6,000,000	5,999,850
Royal Bank of Canada/New York, NY FRN (Canada)	1.555	10/13/17	10,000,000	10,000,000
Royal Bank of Canada/New York, NY FRN (Canada)	1.519	12/8/17	3,000,000	3,000,000
Skandinaviska Enskilda Banken AB/New York, NY FRN	1.659	8/17/17	6,250,000	6,254,154
Skandinaviska Enskilda Banken AB/New York, NY FRN	1.492	11/15/17	8,500,000	8,509,694
Sumitomo Mitsui Banking Corp./New York FRN (Japan)	1.306	11/6/17	8,500,000	8,500,000
Svenska Handelsbanken/New York, NY FRN (Sweden)	1.430	8/1/17	3,000,000	3,000,432
Svenska Handelsbanken/New York, NY FRN (Sweden)	1.422	8/15/17	7,000,000	7,002,189
Svenska Handelsbanken/New York, NY FRN (Sweden)	1.279	12/15/17	8,500,000	8,500,000
Toronto-Dominion Bank/NY (Canada)	1.050	7/17/17	8,000,000	8,000,000
Toronto-Dominion Bank/NY FRN (Canada)	1.532	3/20/18	9,000,000	9,000,000
UBS AG/Stamford, CT	1.180	8/17/17	9,000,000	9,000,000
Wells Fargo Bank, NA FRN	1.596	7/24/17	5,000,000	5,001,216
Wells Fargo Bank, NA FRN	1.505	1/9/18	9,000,000	9,006,149
Wells Fargo Bank, NA FRN	1.367	8/10/17	10,000,000	10,002,308
Total certificates of deposit (cost $229,280,072)				$229,280,072
COMMERCIAL PAPER (22.6%)(a)
	Yield (%)	Maturity date	Principal amount	Value
ABN AMRO Funding USA, LLC	1.082	7/18/17	$4,250,000	$4,247,833
ABN AMRO Funding USA, LLC 144A	1.201	7/10/17	2,500,000	2,499,250
Australia & New Zealand Banking Group, Ltd (Australia)	1.022	7/26/17	8,500,000	8,493,979
BPCE SA (France)	1.227	8/4/17	4,250,000	4,245,083
Canadian Imperial Holdings, Inc.	1.211	7/28/17	7,000,000	6,993,648
Chariot Funding, LLC	1.181	7/18/17	8,250,000	8,245,403
Commonwealth Bank of Australia 144A (Australia)	1.405	7/6/17	4,250,000	4,250,257
Commonwealth Bank of Australia 144A (Australia)	1.187	2/15/18	9,000,000	9,000,000
Commonwealth Bank of Australia 144A (Australia)	1.166	8/4/17	8,250,000	8,253,228
Danske Corp. 144A Ser. A (Denmark)	1.213	8/24/17	4,000,000	3,992,740
Danske Corp. 144A Ser. A (Denmark)	1.195	7/28/17	4,300,000	4,296,162
HSBC Bank PLC 144A (United Kingdom)	1.270	4/13/18	8,000,000	8,000,000
National Australia Bank, Ltd. 144A (Australia)	1.307	11/9/17	3,550,000	3,533,207
National Australia Bank, Ltd. 144A (Australia)	1.273	12/12/17	8,500,000	8,500,000
National Bank of Canada (Canada)	1.133	7/10/17	4,250,000	4,248,799
Nationwide Building Society 144A (United Kingdom)	1.154	8/2/17	4,000,000	3,995,911
Nordea Bank AB (Sweden)	1.229	9/18/17	8,250,000	8,227,822
Nordea Bank AB (Sweden)	1.052	7/25/17	1,400,000	1,399,020
Nordea Bank AB 144A (Sweden)	1.073	7/27/17	2,000,000	1,998,454
NRW.Bank 144A (Germany)	1.206	7/5/17	4,000,000	3,999,464
NRW.Bank 144A (Germany)	1.118	7/21/17	4,250,000	4,247,367
Prudential PLC (United Kingdom)	1.203	9/1/17	2,000,000	1,995,867
Simon Property Group LP	1.274	10/2/17	8,250,000	8,222,933
Skandinaviska Enskilda Banken AB (Sweden)	1.201	7/26/17	1,200,000	1,199,000
Societe Generale SA (France)	1.242	7/31/17	8,250,000	8,241,475
Svenska Handelsbanken AB (Sweden)	1.307	11/6/17	4,000,000	3,981,511
Svenska Handelsbanken AB (Sweden)	1.103	8/1/17	2,300,000	2,297,821
Swedbank AB (Sweden)	1.164	8/23/17	3,750,000	3,743,596
Swedbank AB (Sweden)	1.150	7/3/17	12,750,000	12,749,184
Toronto-Dominion Holdings USA, Inc. 144A (Canada)	1.222	8/14/17	8,095,000	8,082,929
Westpac Banking Corp. 144A (Australia)	1.354	1/8/18	7,000,000	7,000,000
Westpac Banking Corp. 144A (Australia)	1.321	11/2/17	1,500,000	1,501,238
Westpac Banking Corp. 144A (Australia)	1.167	3/2/18	5,000,000	5,000,000
Westpac Banking Corp./NY (Australia)	1.222	8/25/17	11,000,000	10,979,497
Total commercial paper (cost $187,662,678)				$187,662,678
ASSET-BACKED COMMERCIAL PAPER (15.2%)(a)
	Yield (%)	Maturity date	Principal amount	Value
Alpine Securitization, Ltd. (Cayman Islands)	1.274	9/22/17	$4,000,000	$3,988,288
CAFCO, LLC	1.284	9/21/17	4,000,000	3,988,338
Chariot Funding, LLC	0.961	7/6/17	8,250,000	8,248,900
Collateralized Commercial Paper II Co., LLC	1.203	7/5/17	9,000,000	8,998,800
Collateralized Commercial Paper II Co., LLC 144A	1.553	7/24/17	9,000,000	9,001,894
CRC Funding, LLC	1.285	9/28/17	4,000,000	3,987,342
Fairway Finance Co., LLC 144A (Canada)	1.123	8/2/17	12,300,000	12,287,755
Gotham Funding Corp. (Japan)	1.103	8/10/17	4,250,000	4,244,806
Liberty Street Funding, LLC (Canada)	1.346	10/23/17	2,500,000	2,489,392
Liberty Street Funding, LLC (Canada)	1.284	9/18/17	5,000,000	4,985,956
Liberty Street Funding, LLC (Canada)	1.143	7/7/17	9,000,000	8,998,290
Manhattan Asset Funding Co., LLC (Japan)	1.201	7/18/17	8,250,000	8,245,325
Old Line Funding, LLC 144A	1.225	8/15/17	8,500,000	8,487,038
Regency Markets No. 1, LLC	1.121	7/12/17	12,500,000	12,495,722
Regency Markets No. 1, LLC 144A	1.231	7/25/17	4,500,000	4,496,310
Thunder Bay Funding, LLC 144A	1.153	8/21/17	4,250,000	4,243,076
Thunder Bay Funding, LLC 144A	1.062	7/6/17	8,600,000	8,598,734
Victory Receivables Corp. (Japan)	1.211	7/17/17	4,150,000	4,147,768
Victory Receivables Corp. (Japan)	1.072	7/14/17	4,250,000	4,248,358
Total asset-backed commercial paper (cost $126,182,092)				$126,182,092
TIME DEPOSITS (5.7%)(a)
	Yield (%)	Maturity date	Principal amount	Value
Australia & New Zealand Banking Group, Ltd/Cayman Islands (Cayman Islands)	1.150	7/5/17	$17,000,000	$17,000,000
BNP Paribas/Cayman Islands (France)	1.150	7/3/17	8,500,000	8,500,000
Credit Agricole Corporate and Investment Bank/New York (France)	1.060	7/3/17	8,500,000	8,500,000
National Australia Bank/Cayman Islands (Cayman Islands)	1.030	7/3/17	13,000,000	13,000,000
Total time deposits (cost $47,000,000)				$47,000,000
TOTAL INVESTMENTS
Total investments (cost $834,196,842)(b)				$834,196,842

Key to holding's abbreviations
FRN	Floating Rate Notes: the rate shown is the current interest rate or yield at the close of the reporting period

	Notes to the fund's portfolio
	Unless noted otherwise, the notes to the fund's portfolio are for the close of the fund's reporting period, which ran from October 1, 2016 through June 30, 2017 (the reporting period). Within the following notes to the portfolio, references to "ASC 820" represent Accounting Standards Codification 820 Fair Value Measurements and Disclosures, references to "Putnam Management" represent Putnam Investment Management, LLC, the fund's manager, an indirect wholly-owned subsidiary of Putnam Investments, LLC and references to "OTC", if any, represent over-the-counter.
(a)	Percentages indicated are based on net assets of $831,115,000.
(b)	The aggregate identified cost on a financial reporting and tax basis is the same.
	144A after the name of an issuer represents securities exempt from registration under Rule 144A of the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers.
	The dates shown on debt obligations are the original maturity dates.
	DIVERSIFICATION BY COUNTRY
	Distribution of investments by country of risk at the close of the reporting period, excluding collateral received, if any (as a percentage of Portfolio Value):
	United States	56.6%
	Canada	10.1
	Australia	8.5
	Sweden	6.5
	Cayman Islands	4.1
	France	4.0
	Japan	3.5
	United Kingdom	1.7
	Netherlands	1.6
	Norway	1.4
	Denmark	1.0
	Germany	1.0
	Total	100.0%
	Security valuation: Portfolio securities and other investments are valued using policies and procedures adopted by the Board of Trustees. The Trustees have formed a Pricing Committee to oversee the implementation of these procedures and have delegated responsibility for valuing the fund's assets in accordance with these procedures to Putnam Management. Putnam Management has established an internal Valuation Committee that is responsible for making fair value determinations, evaluating the effectiveness of the pricing policies of the fund and reporting to the Pricing Committee.
	The valuation of the fund's portfolio instruments is determined by means of the amortized cost method (which approximates fair value) as set forth in Rule 2a-7 under the Investment Company Act of 1940. The amortized cost of an instrument is determined by valuing it at its original cost and thereafter amortizing any discount or premium from its face value at a constant rate until maturity and is generally categorized as a Level 2 security.
	Repurchase agreements: The fund, or any joint trading account, through its custodian, receives delivery of the underlying securities, the fair value of which at the time of purchase is required to be in an amount at least equal to the resale price, including accrued interest. Collateral for certain tri-party repurchase agreements is held at the counterparty's custodian in a segregated account for the benefit of the fund and the counterparty. Putnam Management is responsible for determining that the value of these underlying securities is at all times at least equal to the resale price, including accrued interest. In the event of default or bankruptcy by the other party to the agreement, retention of the collateral may be subject to legal proceedings.

ASC 820 establishes a three-level hierarchy for disclosure of fair value measurements. The valuation hierarchy is based upon the transparency of inputs to the valuation of the fund's investments. The three levels are defined as follows:
Level 1: Valuations based on quoted prices for identical securities in active markets.
Level 2: Valuations based on quoted prices in markets that are not active or for which all significant inputs are observable, either directly or indirectly.
Level 3: Valuations based on inputs that are unobservable and significant to the fair value measurement.
The following is a summary of the inputs used to value the fund's net assets as of the close of the reporting period:
		Valuation inputs
Investments in securities:	Level 1	Level 2	Level 3
Asset-backed commercial paper	$—	$126,182,092	$—
Certificates of deposit	—	229,280,072	—
Commercial paper	—	187,662,678	—
Repurchase agreements	—	244,072,000	—
Time deposits	—	47,000,000	—
Totals by level	$—	$834,196,842	$—
During the reporting period, transfers within the fair value hierarchy, if any, did not represent, in the aggregate, more than 1% of the fund's net assets measured as of the end of the period. Transfers are accounted for using the end of period pricing valuation method.

	The following table summarizes any derivatives, repurchase agreements and reverse repurchase agreements, at the end of the reporting period, that are subject to an enforceable master netting agreement or similar agreement. For securities lending transactions, if applicable, see note "(AFF)" above, and for borrowing transactions associated with securities sold short, if applicable, see the "Short sales of securities" note above.
		Citigroup Global Markets, Inc.	Goldman, Sachs & Co.	Merrill Lynch, Pierce, Fenner & Smith, Inc.	Total
	Assets:
	Repurchase agreements	$93,000,000	$76,000,000	$75,072,000	$244,072,000
	Total Assets	$93,000,000	$76,000,000	$75,072,000	$244,072,000
	Liabilities:
	Total Liabilities	$—	$—	$—	$—
	Total Financial and Derivative Net Assets	$93,000,000	$76,000,000	$75,072,000	$244,072,000
	Total collateral received (pledged)##†	$93,000,000	$76,000,000	$75,072,000
	Net amount	$—	$—	$—
†	Additional collateral may be required from certain brokers based on individual agreements.
##	Any over-collateralization of total financial and derivative net assets is not shown. Collateral may include amounts related to unsettled agreements.
	For additional information regarding the fund please see the fund's most recent annual or semiannual shareholder report filed on the Securities and Exchange Commission's Web site, www.sec.gov, or visit Putnam's Individual Investor Web site at www.putnaminvestments.com

Item 2. Controls and Procedures:

(a) The registrant's principal executive officer and principal financial officer have concluded, based on their evaluation of the effectiveness of the design and operation of the registrant's disclosure controls and procedures as of a date within 90 days of the filing date of this report, that the design and operation of such procedures are generally effective to provide reasonable assurance that information required to be disclosed by the registrant in this report is recorded, processed, summarized and reported within the time periods specified in the Commission's rules and forms.

(b) Changes in internal control over financial reporting: Not applicable

Item 3. Exhibits:

Separate certifications for the principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the Investment Company Act of 1940, as amended, are filed herewith.

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.

Putnam Money Market Fund

By (Signature and Title):

/s/ Janet C. Smith
Janet C. Smith
Principal Accounting Officer
Date: August 25, 2017

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 (Signature and Title):

/s/ Jonathan S. Horwitz
Jonathan S. Horwitz
Principal Executive Officer
Date: August 25, 2017

By (Signature and Title):

/s/ Janet C. Smith
Janet C. Smith
Principal Financial Officer
Date: August 25, 2017