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UNITEDSTATES
SECURITIESANDEXCHANGECOMMISSION
Washington,D.C.20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED
MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number 811-07156

Name of Fund: BlackRock MuniYield Insured Investment Fund (MFT)

Fund Address: 100 Bellevue Parkway, Wilmington, DE 19809

Name and address of agent for service: Anne F. Ackerley, Chief Executive Officer, BlackRock
MuniYield Insured Investment Fund, 55 East 52nd Street, New York, NY 10055.

Registrant’s telephone number, including area code: (800) 882-0052, Option 4

Date of fiscal year end: 07/31/2010

Date of reporting period: 04/30/2010

Item 1 – Schedule of Investments

Schedule of Investments April 30, 2010 (Unaudited)

BlackRock MuniYield Insured Investment Fund (MFT)
(Percentages shown are based on Net Assets)

     Par   
Municipal Bonds    (000)  Value 
Alabama — 4.2%       
Birmingham Special Care Facilities       
   Financing Authority, RB, Children's       
   Hospital (AGC):       
       6.13%, 6/01/34  $ 1,500  $ 1,631,085 
       6.00%, 6/01/39    2,985  3,240,635 
      4,871,720 
Arizona — 0.5%       
State of Arizona, COP, Department of       
   Administration, Series A (AGM):       
       5.25%, 10/01/28    480  498,038 
       5.00%, 10/01/29    125  126,683 
      624,721 
California — 13.0%       
California State Public Works Board, RB,     
   Various Capital Projects, Series G-1       
   (AGC), 5.25%, 10/01/24    2,000  2,044,660 
California State University, RB,       
   Systemwide, Series A (AGM), 5.00%,     
   11/01/39    1,000  1,011,170 
County of Sacramento California, RB,       
   Senior Series A (AGC), 5.50%,       
   7/01/41    1,400  1,468,376 
Los Angeles Community College District     
   California, GO, Election of 2001,       
   Series A (NPFGC), 5.00%, 8/01/32    2,780  2,842,550 
San Diego Public Facilities Financing       
   Authority, Refunding RB, Series B       
   (AGC), 5.38%, 8/01/34    1,020  1,082,108 
State of California, GO, Various Purpose:     
       (AGC), 5.50%, 11/01/39    3,450  3,613,771 
       (AGM), 5.00%, 6/01/32    3,000  3,021,210 
      15,083,845 
Colorado — 1.2%       
Colorado Health Facilities Authority, RB,     
   Hospital, NCMC Inc. Project, Series B     
   (AGM), 6.00%, 5/15/26    1,300  1,443,520 
Florida — 36.2%       
Broward County Educational Facilities     
   Authority, RB, Educational Facilities,     
   Nova Southeastern University (AGC),     
   5.00%, 4/01/31    1,720  1,737,475 
City of Boynton Beach Florida,       
   Refunding RB (FGIC), 6.25%,       
   11/01/20 (a)    700  855,834 

     Par   
Municipal Bonds    (000)  Value 
Florida (continued)       
City of Jacksonville Florida, Refunding     
   RB (NPFGC), 5.25%, 10/01/32  $ 1,455  $ 1,474,701 
City of Lakeland Florida, Refunding RB,     
   Series A (NPFGC), 5.00%, 10/01/28  1,075  1,083,299 
City of Port St. Lucie Florida, RB       
   (NPFGC), 5.25%, 9/01/24    1,055  1,072,081 
County of Lee Florida, RB, Series A, AMT     
   (AGM), 6.00%, 10/01/29    1,000  1,015,060 
County of Miami-Dade Florida, RB:       
CAB, Sub-Series A (NPFGC), 5.19%,     
       10/01/31 (b)    4,375  1,107,444 
Miami International Airport, Series     
       A, AMT (AGM), 5.25%, 10/01/41    1,200  1,185,384 
Miami International Airport, Series     
       A, AMT (AGM), 5.50%, 10/01/41    2,400  2,427,264 
       Series A, AMT (AGM), 5.00%,       
       10/01/33    4,505  4,342,279 
County of Orange Florida, Refunding RB:     
       (AMBAC), 5.00%, 10/01/29    2,190  2,236,778 
Series A (NPFGC), 5.13%, 1/01/23  1,000  1,046,000 
County of Osceola Florida, RB, Series A     
   (NPFGC), 5.50%, 10/01/27    1,100  1,123,639 
County of St. John's Florida, RB (AGM),     
   5.00%, 10/01/31    2,135  2,204,345 
Florida Housing Finance Corp., HRB,       
   Brittany Rosemont Apartments, Series     
   C-1, AMT (AMBAC), 6.75%, 8/01/14  715  715,872 
Florida Housing Finance Corp., RB,       
   Homeowner Mortgage, Series 11,       
   AMT (AGM), 5.95%, 1/01/32    1,440  1,440,907 
Florida Housing Finance Corp.,       
   Refunding RB, Homeowner Mortgage,     
   Series 4, AMT (AGM), 6.25%,       
   7/01/22    230  239,087 
Jacksonville Economic Development       
   Commission, RB, Mayo Clinic, Series     
   B (NPFGC), 5.50%, 11/15/36    750  765,278 
Miami-Dade County Expressway       
   Authority Florida, RB, Series B       
   (NPFGC), 5.25%, 7/01/27    1,000  1,026,630 
Miami-Dade County IDA, RB, BAC       
   Funding Corp. Project, Series A       
   (AMBAC), 5.38%, 10/01/30    1,655  1,704,667 
Orange County Educational Facilities       
   Authority, Refunding RB, Rollins       
   College Project (AMBAC), 5.50%,       
   12/01/32    4,765  4,823,419 

Portfolio Abbreviations

To simplify the listings of portfolio holdings in the Schedule of Investments, the names and descriptions of many of the securities have been abbreviated
according to the following list:

AGC  Assured Guaranty Corp.  FGIC  Financial Guaranty Insurance Co. 
AGM  Assured Guaranty Municipal Corp.  GARB  General Airport Revenue Bonds 
AMBAC  American Municipal Bond Assurance Corp.  GNMA  Government National Mortgage Association 
AMT  Alternative Minimum Tax (subject to)  GO  General Obligation Bonds 
BHAC  Berkshire Hathaway Assurance Corp.  HRB  Housing Revenue Bonds 
CAB  Capital Appreciation Bonds  IDA  Industrial Development Authority 
CIFG  CDC IXIS Financial Guaranty  ISD  Independent School District 
COP  Certificates of Participation  NPFGC  National Public Finance Guarantee Corp. 
EDA  Economic Development Authority  RB  Revenue Bonds 
ERB  Education Revenue Bonds  S/F  Single-Family 

BLACKROCK MUNIYIELD INSURED INVESTMENT FUND

APRIL 30, 2010

1

Schedule of Investments (continued)

BlackRock MuniYield Insured Investment Fund (MFT)
(Percentages shown are based on Net Assets)

     Par   
Municipal Bonds    (000)  Value 
Florida (concluded)       
Palm Beach County School District, COP,     
   Refunding, Series D (AGM), 5.25%,       
   8/01/21  $ 2,000  $ 2,117,060 
Santa Rosa County School Board, COP,     
   Refunding, Series 2 (NPFGC), 5.25%,     
   2/01/26    2,000  2,093,720 
St. Lucie West Services District, RB       
   (NPFGC), 5.25%, 10/01/34    1,000  1,015,010 
Village Center Community Development     
   District, RB, Series A (NPFGC):       
       5.38%, 11/01/34    1,640  1,464,979 
       5.13%, 11/01/36    1,000  857,520 
Volusia County IDA, RB, Student       
   Housing, Stetson University Project,       
   Series A (CIFG), 5.00%, 6/01/35    1,000  855,000 
      42,030,732 
Georgia — 4.0%       
County of Fulton Georgia, RB (NPFGC),     
   5.25%, 1/01/35    1,000  1,039,480 
Gwinnett County Hospital Authority,       
   Refunding RB, Gwinnett Hospital       
   System, Series D (AGM), 5.50%,       
   7/01/41    1,375  1,397,660 
Metropolitan Atlanta Rapid Transit       
   Authority, RB, Third Indenture, Series     
   B (AGM), 5.00%, 7/01/34    2,100  2,200,317 
      4,637,457 
Illinois — 11.2%       
Chicago Board of Education Illinois, GO,     
   Refunding, Chicago School Reform       
   Board, Series A (NPFGC), 5.50%,       
   12/01/26    825  924,718 
Chicago Transit Authority, RB, Federal     
   Transit Administration Section 5309,     
   Series A (AGC), 6.00%, 6/01/26    1,400  1,606,108 
City of Chicago Illinois, GO, Refunding,     
   Projects, Series A (AGM):       
       5.00%, 1/01/28    945  996,058 
       5.00%, 1/01/29    1,465  1,533,533 
       5.00%, 1/01/30    585  609,090 
City of Chicago Illinois, RB, General,       
   Third Lien, Series C (AGM), 5.25%,       
   1/01/35    835  864,392 
City of Chicago Illinois, Refunding RB,       
   Second Lien (NPFGC), 5.50%,       
   1/01/30    895  987,409 
Illinois Municipal Electric Agency, RB,       
   Series A (NPFGC), 5.25%, 2/01/28    1,565  1,627,960 
State of Illinois, RB:       
       (AGM), 5.00%, 6/15/27    1,000  1,024,450 
       Build Illinois, Series B, 5.25%,       
       6/15/28    1,750  1,859,357 

   Par   
Municipal Bonds  (000)  Value 
Illinois (concluded)     
Village of Schaumburg Illinois, GO,     
   Series B (NPFGC), 5.00%, 12/01/38 $  1,000  $ 1,013,850 
    13,046,925 
Indiana — 4.4%     
Indiana Municipal Power Agency, RB,     
   Series A (NPFGC), 5.00%, 1/01/42  1,485  1,489,069 
Indianapolis Local Public Improvement     
   Bond Bank, Refunding RB,     
   Waterworks Project, Series A (AGC),     
   5.50%, 1/01/38  3,310  3,572,351 
    5,061,420 
Iowa — 1.1%     
Iowa Finance Authority, Refunding RB,     
   Iowa Health System (AGC), 5.25%,     
   2/15/29  1,190  1,227,092 
Kentucky — 1.1%     
Kentucky Municipal Power Agency, RB,     
   Prairie State Project, Series A (BHAC),     
   5.25%, 9/01/42  1,250  1,292,950 
Louisiana — 1.9%     
Louisiana State Citizens Property     
   Insurance Corp., RB, Series C-3 (AGC),     
   6.13%, 6/01/25  1,405  1,559,171 
New Orleans Aviation Board Louisiana,     
   Refunding RB (AGC), Restructuring     
   GARB:     
       Series A-1, 6.00%, 1/01/23  375  426,229 
       Series A-2, 6.00%, 1/01/23  160  181,857 
    2,167,257 
Maine — 1.0%     
City of Portland Maine, RB, General     
   (AGM), 5.25%, 1/01/35  1,125  1,153,215 
Michigan — 17.2%     
City of Detroit Michigan, RB:     
       Second Lien, Series B (AGM),     
       6.25%, 7/01/36  1,800  1,965,114 
       Second Lien, Series B (AGM),     
       7.00%, 7/01/36  200  230,386 
       Second Lien, Series B (NPFGC),     
       5.50%, 7/01/29  1,640  1,650,562 
       Senior Lien, Series B (AGM), 7.50%,     
       7/01/33  1,000  1,200,760 
       Senior Lien, Series B (BHAC),     
       5.50%, 7/01/35  3,750  3,902,287 
       System, Second Lien, Series A     
       (BHAC), 5.50%, 7/01/36  2,265  2,333,901 
City of Detroit Michigan, Refunding RB:     
       Second Lien, Series E (BHAC),     
       5.75%, 7/01/31  2,270  2,406,291 
       Senior Lien, Series C-1 (AGM),     
       7.00%, 7/01/27  1,650  1,921,904 

2 BLACKROCK MUNIYIELD INSURED INVESTMENT FUND

APRIL 30, 2010

Schedule of Investments (continued)

BlackRock MuniYield Insured Investment Fund (MFT)
(Percentages shown are based on Net Assets)

  Par   
Municipal Bonds  (000)  Value 
Michigan (concluded)     
Michigan State Building Authority, RB,     
   Facilities Program, Series H (AGM),     
   5.00%, 10/15/26  $ 375  $ 380,925 
Michigan State Building Authority,     
   Refunding RB, Facilities Program,     
   Series I (AGC):     
       5.25%, 10/15/22  1,350  1,465,614 
       5.25%, 10/15/24  615  656,254 
       5.25%, 10/15/25  310  328,479 
Royal Oak Hospital Finance Authority     
   Michigan, Refunding RB, William     
   Beaumont Hospital, 8.25%, 9/01/39  1,265  1,493,117 
    19,935,594 
Minnesota — 2.9%     
City of Minneapolis Minnesota,     
   Refunding RB, Fairview Health     
   Services, Series B (AGC), 6.50%,     
   11/15/38  3,000  3,365,040 
Nevada — 2.1%     
County of Clark Nevada, RB, Las Vegas-     
   McCarran International Airport,     
 Series A (AGC), 5.25%, 7/01/39  2,355  2,397,720 
New Jersey — 2.3%     
New Jersey EDA, RB, School Facilities     
   Construction, Series Z (AGC), 6.00%,     
   12/15/34  1,000  1,131,610 
New Jersey Health Care Facilities     
   Financing Authority, RB, Virtua Health     
   (AGC), 5.50%, 7/01/38  1,400  1,484,700 
    2,616,310 
New York — 5.9%     
New York City Transitional Finance     
   Authority, RB, Fiscal 2009:     
       Series S-3, 5.25%, 1/15/39  1,000  1,061,620 
       Series S-4 (AGC), 5.50%, 1/15/29  2,000  2,221,760 
New York State Dormitory Authority,     
   ERB, Series B, 5.25%, 3/15/38  3,250  3,510,488 
    6,793,868 
Ohio — 1.4%     
Ohio Higher Educational Facility     
   Commission, Refunding RB, Summa     
   Health System, 2010 Project (AGC),     
   5.25%, 11/15/40 (c)  1,650  1,615,779 
Oregon — 0.4%     
Medford Hospital Facilities Authority,     
   RB, Asante Health System, Series A     
   (AGC), 5.00%, 8/15/40  510  511,510 
Pennsylvania — 1.3%     
Pennsylvania Turnpike Commission, RB,     
   Sub-Series B (AGM), 5.25%, 6/01/39  1,455  1,516,852 

       Par   
Municipal Bonds  (000)             Value 
Puerto Rico — 1.4%     
Puerto Rico Sales Tax Financing Corp.,     
   RB, First Sub-Series A, 6.38%,     
   8/01/39  $ 1,425  $ 1,600,033 
Texas — 16.7%     
City of Dallas Texas, Refunding RB     
   (AGC), 5.25%, 8/15/38  850  876,410 
City of Houston Texas, Refunding RB,     
   Combined, First Lien, Series A (AGC):     
       6.00%, 11/15/35  2,700  3,097,440 
       6.00%, 11/15/36  2,055  2,352,482 
       5.38%, 11/15/38  1,000  1,083,710 
County of Bexar Texas, RB, Venue     
   Project, Motor Vehicle Rental (BHAC):     
       5.00%, 8/15/27  1,040  1,099,176 
       5.00%, 8/15/28  1,090  1,145,001 
       5.00%, 8/15/39  880  905,810 
Frisco ISD Texas, GO, School Building     
   (AGC), 5.50%, 8/15/41  700  759,829 
Harris County Health Facilities     
   Development Corp., Refunding RB,     
   Memorial Hermann Healthcare     
   System, B, 7.25%, 12/01/35  500  563,585 
Lower Colorado River Authority,     
   Refunding RB, LCRA Transmission     
   Services Project (AGC), 5.50%,     
   5/15/36  1,155  1,223,272 
Lubbock Cooper ISD Texas, GO, School     
   Building (AGC), 5.75%, 2/15/42  500  535,925 
North Texas Tollway Authority, RB,     
   System, First Tier, Series K-1 (AGC),     
   5.75%, 1/01/38  1,400  1,514,982 
North Texas Tollway Authority,     
   Refunding RB, System, First Tier,     
   Series A:     
       (AGC), 5.75%, 1/01/40  1,500  1,611,315 
       (NPFGC), 5.13%, 1/01/28  2,500  2,564,350 
    19,333,287 
Utah — 2.5%     
City of Riverton Utah, RB, IHC Health     
   Services Inc., 5.00%, 8/15/41  1,670  1,698,440 
Tarrant County Cultural Education     
   Facilities Finance Corp., Refunding     
   RB, Christus Health, Series A (AGC),     
   6.50%, 7/01/37  1,100  1,220,549 
    2,918,989 
Virginia — 1.1%     
Virginia Public School Authority, RB,     
   School Financing, 6.50%, 12/01/35  1,100  1,271,303 
Total Municipal Bonds – 135.0%    156,517,139 

BLACKROCK MUNIYIELD INSURED INVESTMENT FUND

APRIL 30, 2010

3

Schedule of Investments (continued)

BlackRock MuniYield Insured Investment Fund (MFT)
(Percentages shown are based on Net Assets)

Municipal Bonds Transferred to Tender  Par   
Option Bond Trusts (d)  (000)  Value 
District of Columbia — 0.7%     
District of Columbia Water & Sewer     
   Authority, RB, Series A, 6.00%,     
   10/01/35  $ 750  $ 845,005 
Florida — 8.9%     
City of Jacksonville Florida, RB, Better     
   Jacksonville (NPFGC), 5.00%,     
   10/01/27  1,320  1,352,419 
Hillsborough County Aviation Authority,     
   RB, Series A, AMT (AGC), 5.50%,     
   10/01/38  2,499  2,531,078 
Lee County Housing Finance Authority,     
   RB, Multi-County Program, Series A-2,     
   AMT (GNMA), 6.00%, 9/01/40  1,035  1,120,739 
Manatee County Housing Finance     
   Authority, RB, Series A, AMT (GNMA),     
   5.90%, 9/01/40  891  926,833 
South Broward Hospital District, RB,     
   Hospital (NPFGC), 5.63%,     
 5/01/12 (e)  4,000  4,400,920 
    10,331,989 
Kentucky — 0.9%     
Kentucky State Property & Building     
   Commission, Refunding RB, Project     
   No. 93 (AGC), 5.25%, 2/01/27  1,002  1,082,873 
Nevada — 3.8%     
Clark County Water Reclamation     
   District, GO:     
Limited Tax, 6.00%, 7/01/38  2,010  2,250,497 
Series B, 5.50%, 7/01/29  1,994  2,188,344 
    4,438,841 
New Jersey — 1.4%     
New Jersey State Housing & Mortgage     
   Finance Agency, RB, S/F Housing,     
   Series CC, 5.25%, 10/01/29  1,620  1,670,416 
New York — 2.8%     
New York City Municipal Water Finance     
   Authority, RB, Series FF-2, 5.50%,     
   6/15/40  1,095  1,217,413 
New York State Thruway Authority, RB,     
   Series G (AGM), 5.00%, 1/01/32  2,000  2,052,960 
    3,270,373 
Texas — 2.5%     
City of San Antonio Texas, Refunding     
   RB, Series A, 5.25%, 2/01/31  2,609  2,844,150 

    Value 
Total Municipal Bonds Transferred to     
Tender Option Bond Trusts – 21.0%  $ 24,483,647 
Total Long-Term Investments     
(Cost – $174,660,218) – 156.0%                                   181,000,786
Short-Term Securities  Shares   
FFI Institutional Tax-Exempt Fund,     
0.25% (f)(g)  4,350,998  4,350,998 
Total Short-Term Securities     
(Cost – $4,350,998) – 3.7%    4,350,998 
Total Investments     
(Cost – $179,011,216*) – 159.7%    185,351,784 
Liabilities in Excess of Other Assets – (0.1)%  (60,026) 
Liability for Trust Certificates, Including Interest   
Expense and Fees Payable – (10.9)%    (12,711,193) 
Preferred Shares, at Redemption Value – (48.7)%  (56,530,350) 
Net Assets Applicable to Common Shares – 100.0% $  116,050,215 

* The cost and unrealized appreciation (depreciation) of investments as of
April 30, 2010, as computed for federal income tax purposes, were as

Aggregate follows: cost  $ 166,324,496 
Gross unrealized appreciation  $ 7,413,507 
Gross unrealized depreciation  (1,087,598) 
Net unrealized appreciation  $ 6,325,909 

(a) Security is collateralized by Municipal or US Treasury obligations.
(b) Represents a zero-coupon bond. Rate shown reflects the current yield as
of report date.
(c) When-issued security. Unsettled when-issued transactions were as
follows:

    Unrealized 
Counterparty  Value  Appreciation 
JPMorgan Chase Securities  $ 1,615,779  $ 7,425 

(d) Securities represent bonds transferred to a tender option bond trust in
exchange for which the Fund acquired residual interest certificates.
These securities serve as collateral in a financing transaction.
(e) US government securities, held in escrow, are used to pay interest on this
security as well as to retire the bond in full at the date indicated, typically
at a premium to par.

4 BLACKROCK MUNIYIELD INSURED INVESTMENT FUND

APRIL 30, 2010

Schedule of Investments (concluded)

BlackRock MuniYield Insured Investment Fund (MFT)

(f) Investments in companies considered to be an affiliate of the Fund 
     during the period, for purposes of Section 2(a)(3) of the Investment 
     Company Act of 1940, were as follows:     
  Shares Held    Shares Held   
  at July 31,  Net  at April 30,   
   Affiliate  2009  Activity  2010  Income 
   FFI         
     Institutional         
     Tax-Exempt         
     Fund  2,301,550  2,049,448  4,350,998  $10,888 

(g) Represents the current yield as of report date.

• Fair Value Measurements - Various inputs are used in determining the fair

value of investments, which are as follows:

• Level 1 — price quotations in active markets/exchanges for identical
assets and liabilities

• Level 2 — other observable inputs (including, but not limited to: quoted
prices for similar assets or liabilities in markets that are active, quoted
prices for identical or similar assets or liabilities in markets that are not
active, inputs other than quoted prices that are observable for the
assets or liabilities (such as interest rates, yield curves, volatilities,
prepayment speeds, loss severities, credit risks and default rates) or
other market-corroborated inputs)

• Level 3 — unobservable inputs based on the best information available
in the circumstances, to the extent observable inputs are not available
(including the Fund's own assumptions used in determining the fair
value of investments)

The inputs or methodologies used for valuing securities are not necessarily
an indication of the risk associated with investing in those securities. For
information about the Fund's policy regarding valuation of investments and
other significant accounting policies, please refer to the Fund’s most recent
financial statements as contained in its semi-annual report.

The following table summarizes the inputs used as of April 30, 2010 in
determining the fair valuation of the Fund's investments:

Investments in Securities
Valuation Inputs  Level 1  Level 2  Level 3  Total 
Assets:         
Long-Term         
 Investments1   —   $ 181,000,786  —  $ 181,000,786 
Short-Term         
 Securities  $ 4,350,998  —  —  4,350,998 
Total  $ 4,350,998 $  181,000,786  —  $ 185,351,784 

1 See above Schedule of Investments for values in each state or political subdivision.

BLACKROCK MUNIYIELD INSURED INVESTMENT FUND

APRIL 30, 2010

5

Item 2 – Controls and Procedures

2(a) – The registrant's principal executive and principal financial officers or persons performing
similar functions have concluded that the registrant's disclosure controls and procedures (as
defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the
“1940 Act”)) are effective as of a date within 90 days of the filing of this report based on the
evaluation of these controls and procedures required by Rule 30a-3(b) under the 1940 Act
and Rule 13(a)-15(b) under the Securities Exchange Act of 1934, as amended.

2(b) – There were no changes in the registrant's internal control over financial reporting (as defined
in Rule 30a-3(d) under the 1940 Act) that occurred during the registrant's last fiscal quarter
that have materially affected, or are reasonably likely to materially affect, the registrant's
internal control over financial reporting.

Item 3 – Exhibits

Certifications – Attached hereto

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.

BlackRock MuniYield Insured Investment Fund

By: /s/ Anne F. Ackerley
Anne F. Ackerley
Chief Executive Officer of
BlackRock MuniYield Insured Investment Fund

Date: June 28, 2010

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/ Anne F. Ackerley
Anne F. Ackerley
Chief Executive Officer (principal executive officer) of
BlackRock MuniYield Insured Investment Fund

Date: June 28, 2010

By: /s/ Neal J. Andrews
Neal J. Andrews
Chief Financial Officer (principal financial officer) of
BlackRock MuniYield Insured Investment Fund

Date: June 28, 2010