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 13a-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 Build America Bond Trust

	By:	/s/ John M. Perlowski
		John M. Perlowski
		Chief Executive Officer (principal executive officer) of
		BlackRock Build America Bond Trust

	Date: June 22, 2012

	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/ John M. Perlowski
		John M. Perlowski
		Chief Executive Officer (principal executive officer) of
		BlackRock Build America Bond Trust

	Date: June 22, 2012

	By:	/s/ Neal J. Andrews
		Neal J. Andrews
		Chief Financial Officer (principal financial officer) of
		BlackRock Build America Bond Trust

	Date: June 22, 2012



Schedule of Investments April 30, 2012 (Unaudited)	BlackRock Build America Bond Trust (BBN)
Schedule of Investments April 30, 2012 (Unaudited)	(Percentages shown are based on Net Assets)


Municipal Bonds	Par (000)		Value
Arizona — 3.0%
Phoenix Civic Improvement Corp., RB, Series C (NPFGC), 6.00%, 7/01/35	$	10,000	$	10,440,100
Salt River Project Agricultural Improvement & Power District, RB, Build America Bonds, 4.84%, 1/01/41 (a)		25,000		28,933,750
				39,373,850
California — 31.1%
Alameda County Joint Powers Authority, RB, Build America Bonds, Recovery, Series Z, 7.05%, 12/01/44 (a)		13,300		16,566,613
Bay Area Toll Authority, RB, Build America Bonds:
Series S-1, 6.92%, 4/01/40		13,700		18,488,150
Series S-3, 6.91%, 10/01/50		14,000		19,119,800
California State Public Works Board, RB, Build America Bonds, Series G-2, 8.36%, 10/01/34		18,145		22,579,638
California State University, RB, Build America Bonds, 6.48%, 11/01/41		2,125		2,548,959
City of San Jose CA, Refunding ARB, Series B (AGM), 6.60%, 3/01/41		10,000		10,659,900
County of Sonoma California, Refunding RB, Series A, 6.00%, 12/01/29		14,345		16,081,319
Los Angeles Community College District California, GO, Build America Bonds, 6.60%, 8/01/42 (a)		10,000		13,069,800
Los Angeles Department of Water & Power, RB, Build America Bonds:
6.17%, 7/01/40 (a)		37,500		42,606,750
7.00%, 7/01/41		17,225		20,520,315
Metropolitan Water District of Southern California, RB, Build America Bonds, 6.95%, 7/01/40 (a)		12,000		14,461,560
Orange County Local Transportation Authority, RB, Build America Bonds, Series A, 6.91%, 2/15/41 (a)		5,000		6,810,300
Palomar Community College District, GO, Build America Bonds, 7.19%, 8/01/45		7,500		8,772,225
Rancho Water District Financing Authority, RB, Build America Bonds, 6.34%, 8/01/40 (a)		20,000		21,397,400
Riverside Community College District, GO, Build America Bonds, Series EL, 7.02%, 8/01/40		11,000		12,282,160
San Diego County Regional Airport Authority, Refunding RB, Build America Bonds, Series SU, 6.63%, 7/01/40		31,000		33,655,460
San Francisco City & County Public Utilities Commission, RB, Build America Bonds, Series D, 6.00%, 11/01/40 (a)		21,255		25,876,687

Municipal Bonds	Par (000)		Value
California (concluded)
State of California, GO, Build America Bonds:
7.63%, 3/01/40	$	8,950	$	11,927,575
7.60%, 11/01/40		15,000		19,989,150
Various Purpose, 7.55%, 4/01/39		9,035		11,947,703
University of California, RB, Build America Bonds (a):
5.95%, 5/15/45		24,000		29,130,240
6.30%, 5/15/50		26,310		30,605,897
				409,097,601
Colorado — 3.6%
Denver Public Schools, COP, Refunding, Series B, 7.02%, 12/15/37		6,000		7,583,640
Regional Transportation District, COP, Build America Bonds, 7.67%, 6/01/40		28,000		34,317,360
State of Colorado, COP, Build America Bonds, Series E, 7.02%, 3/15/31		5,000		5,688,450
				47,589,450
District of Columbia — 2.6%
Metropolitan Washington Airports Authority, RB, Build America Bonds:
7.46%, 10/01/46		4,525		5,277,100
Series D, 8.00%, 10/01/47		10,750		13,182,725
Washington Convention & Sports Authority, Refunding RB, Series C, 7.00%, 10/01/40		15,000		15,676,950
				34,136,775
Florida — 2.4%
City of Sunrise Florida, RB, Build America Bonds, Series B, 5.91%, 10/01/35 (a)		25,000		27,525,500
County of Pasco Florida, RB, Build America Bonds, Series B, 6.76%, 10/01/39		1,500		1,647,285
Town of Davie Florida, RB, Build America Bonds, Series B (AGM), 6.85%, 10/01/40		2,500		2,749,450
				31,922,235
Georgia — 5.3%
Municipal Electric Authority of Georgia, Refunding RB, Build America Bonds:
6.66%, 4/01/57		20,665		23,246,058
Series PL, 6.64%, 4/01/57		32,084		36,524,426
Series PL, 7.06%, 4/01/57		10,000		10,575,000
				70,345,484



Schedule of Investments (continued)	BlackRock Build America Bond Trust (BBN)
Schedule of Investments (continued)	(Percentages shown are based on Net Assets)


Municipal Bonds	Par (000)		Value
Hawaii — 2.7%
University of Hawaii, RB, Build America Bonds:
Series A, 6.03%, 10/01/40	$	2,500	$	2,681,075
Series B, 6.03%, 10/01/40		30,500		32,471,825
				70,345,484
Illinois — 20.3%
Chicago Board of Education, GO, Build America Bonds:
6.52%, 12/01/40		27,300		32,913,699
Series E, 6.14%, 12/01/39		3,495		3,992,583
Chicago Transit Authority, RB:
Build America Bonds, Series B, 6.20%, 12/01/40		16,015		18,728,422
Series A, 6.90%, 12/01/40		4,075		4,953,529
Series B, 6.90%, 12/01/40		4,900		5,956,391
City of Chicago Illinois, GO, Build America Bonds:
Direct Payment, Series B, 7.52%, 1/01/40		1,000		1,267,790
Recovery, Series Z, 6.26%, 1/01/40		22,180		23,942,423
City of Chicago Illinois, RB, Build America Bonds:
6.85%, 1/01/38 (a)		30,110		33,834,607
6.40%, 1/01/40		1,500		1,896,720
6.74%, 11/01/40 (a)		15,250		19,681,040
City of Chicago Illinois, Refunding RB, Build America Bonds, 6.90%, 1/01/40 (a)		36,000		44,810,640
Cook County Illinois, GO, Build America Bonds, Series D, 6.23%, 11/15/34		5,000		5,642,300
Illinois Finance Authority, RB, Series A, 5.75%, 8/15/34		5,000		5,402,900
Illinois Municipal Electric Agency, RB, Build America Bonds, 7.29%, 2/01/35		15,000		18,983,400
Northern Illinois Municipal Power Agency, RB, Build America Bonds, 7.82%, 1/01/40		5,000		6,867,300
State of Illinois, GO, Build America Bonds, 7.35%, 7/01/35		34,295		39,087,726
				267,961,470
Indiana — 2.7%
Indiana Finance Authority, RB, Build America Bonds, 6.60%, 2/01/39		7,900		10,209,802
Indiana Municipal Power Agency, RB, Build America Bonds, Direct Payment, 5.59%, 1/01/42		22,290		24,787,149
				34,996,951
Iowa — 0.2%
Iowa Tobacco Settlement Authority, Refunding RB, Asset-Backed, Series A, 6.50%, 6/01/23		2,640		2,502,218

Municipal Bonds	Par (000)		Value
Kentucky — 1.6%
City of Wickliffe, RB, Westvaco Corp, Project, 7.67%, 1/15/27 (b)	$	9,400	$	9,751,090
Kentucky State Property & Building Commission, RB, Build America Bonds, Series C, 5.92%, 11/01/30		10,000		10,867,700
				20,618,790
Maine — 0.4%
Maine Health & Higher Educational Facilities Authority, 6.75%, 7/01/36		5,000		5,621,200
Maryland — 0.1%
Maryland Community Development Administration, RB, Residential, Series I, 6.50%, 3/01/43		1,000		1,020,620
Massachusetts — 1.5%
Commonwealth of Massachusetts, RB, Build America Bonds, Recovery, Series Z, 5.73%, 6/01/40 (a)		5,000		6,432,050
Massachusetts HFA, Refunding RB, Series D, 7.02%, 12/01/42		12,000		13,662,240
				20,094,290
Michigan — 1.9%
Detroit City School District, GO, Build America Bonds (Q-SBLF), 6.85%, 5/01/40		10,000		10,479,100
Michigan State University, RB, Build America Bonds, 6.17%, 2/15/50		5,500		6,625,520
State of Michigan, RB, Build America Bonds, Series B, 7.63%, 9/15/27		2,000		2,461,200
Wayne County, RB, Recovery Zone Economic Development Bonds, 10.00%, 12/01/40		5,000		5,729,100
				25,294,920
Minnesota — 1.2%
Southern Minnesota Municipal Power Agency, Refunding RB, Build America Bonds, 5.93%, 1/01/43		8,000		8,798,320
Western Minnesota Municipal Power Agency, RB, Build America Bonds, 6.77%, 1/01/46		5,000		6,444,700
				15,243,020
Mississippi — 0.5%
Mississippi Development Bank, RB, Build America Bonds, 6.41%, 1/01/40		5,000		6,209,650
Missouri — 1.8%
Missouri Joint Municipal Electric Utility Commission, RB, Build America Bonds, 7.73%, 1/01/39		11,000		14,353,240
University of Missouri, RB, Build America Bonds, 5.79%, 11/01/41 (a)		7,000		8,860,880
				23,214,120



Schedule of Investments (continued)	BlackRock Build America Bond Trust (BBN)
Schedule of Investments (continued)	(Percentages shown are based on Net Assets)


*	As of April 30, 2012, gross unrealized appreciation and gross unrealized depreciation based on cost for federal income tax purposes were as follows:


Tax Cost	$	1,602,068,573
Gross unrealized appreciation	$	241,376,265
Gross unrealized depreciation		(193,433	)
Net unrealized appreciation	$	241,182,832


(a)	All or a portion of security has been pledged as collateral in connection with open reverse repurchase agreements.

(b)	Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933. These securities may be resold in transactions exempt from registration to qualified institutional investors.

(c)	Investments in companies considered to be an affiliate of the Trust during the period, for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:



Affiliate	Shares Held at July 31, 2011		Net Activity		Shares Held at April 30, 2012		Income

BlackRock Liquidity Funds, TempFund, Institutional Class		1,448,706		536,017		1,984,723	$	11,498


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:

AGM	Assured Guaranty Municipal Corp.
AMT	Alternative Minimum Tax (subject to)
ARB	Airport Revenue Bonds
COP	Certificates of Participation
EDA	Economic Development Authority
GO	General Obligation Bonds
HFA	Housing Finance Agency
ISD	Independent School District
NPFGC	National Public Finance Guarantee Corp.
PSF-GTD	Permanent School Fund Guaranteed
Q-SBLF	Qualified School Bond Loan Fund
RB	Revenue Bonds


•	Reverse repurchase agreements outstanding as of April 30, 2012 were as follows:


Counterparty	Interest Rate	Trade Date	Maturity Date¹	Net Closing Amount		Face Amount
Deutsche Bank Securities, Inc.	0.55%	3/05/12	Open	$	2,061,794	$	2,060,000
Credit Suisses Securities (USA) LLC	0.50%	3/15/12	Open		11,512,510		11,505,000
Credit Suisses Securities (USA) LLC	0.50%	3/16/12	Open		9,493,561		9,487,500
Credit Suisses Securities (USA) LLC	0.50%	3/21/12	Open		180,096,647		179,994,150
Deutsche Bank Securities, Inc.	0.50%	3/21/12	Open		48,465,082		48,437,500
Deutsche Bank Securities, Inc.	0.55%	3/21/12	Open		56,794,028		56,758,475
Barclays Capital, Inc.	0.50%	3/29/12	Open		13,517,330		13,511,138
Barclays Capital, Inc	0.50%	4/03/12	Open		30,116,808		30,105,100
Citigroup Global Markets, Inc.	0.60%	4/04/12	Open		18,250,114		18,241,905
Barclays Capital, Inc.	0.55%	4/16/12	Open		15,803,621		15,800,000
Barclays Capital, Inc.	0.50%	4/18/12	Open		88,617,398		88,601,400
Credit Suisses Securities (USA) LLC	0.50%	4/18/12	Open		57,434,537		57,424,169
Deutsche Bank Securities, Inc.	0.55%	4/30/12	Open		28,535,436		28,535,000
Total				$	560,698,866	$	560,461,337


	¹	Certain agreements have no stated maturity and can be terminated by either party at any time.


•	Financial futures contracts sold as of April 30, 2012 were as follows:


Contracts	Issue	Exchange	Expiration	Notional Value		Unrealized Depreciation
320	10-Year US Treasury Note	Chicago Board of Trade	June 2012	$	42,330,000	$	(625,608	)
1,445	30-Year US Treasury Bond	Chicago Board of Trade	June 2012	$	206,454,375		(3,290,246	)
Total						$	(3,915,854	)



BLACKROCK BUILD AMERICA BOND TRUST	APRIL 30, 2012	1



BLACKROCK BUILD AMERICA BOND TRUST	APRIL 30, 2012	2



BLACKROCK BUILD AMERICA BOND TRUST	APRIL 30, 2012	3


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


•	Fair Value Measurements - Various inputs are used in determining the fair value of investments and derivative financial instruments. These inputs are categorized into a disclosure hierarchy consisting of three broad levels for financial reporting purposes as follows:

	•	Level 1 — unadjusted 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 Trust’s own assumptions used in determining the fair value of investments and derivative financial instruments)


Valuation Inputs	Level 1		Level 2		Level 3		Total
Assets:
Investments:
Long-Term Investments¹		—	$	1,841,266,682		—	$	1,841,266,682
Short-Tem Securities	$	1,984,723		—		—		1,984,723
Total	$	1,984,723	$	1,841,266,682		—	$	1,843,251,405


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



Schedule of Investments (concluded)	BlackRock Build America Bond Trust (BBN)


²	Derivative financial instruments are financial futures contracts, which are valued at the unrealized appreciation/depreciation on the instrument.