Schedule of Investments (continued)

BlackRock Maryland Municipal Bond Trust (BZM)

(Percentages shown are based on Net Assets)

Value

Total Investments (Cost - $48,380,152*) – 105.9%

$

50,705,630

Other Assets Less Liabilities – 32.5%

15,569,475

Liability for TOB Trust Certificates, Including Interest
Expense and Fees Payable – (5.0)%

(2,401,479

)

AMPS, at Redemption Value – (33.4)%

(16,000,982

)

Net Assets Applicable to Common Shares – 100.0%

$

47,872,644

*

As of May 31, 2012, gross unrealized appreciation and gross unrealized depreciation based on cost for federal income tax purposes were as follows:

Tax cost

$

45,896,511

Gross unrealized appreciation

$

2,464,288

Gross unrealized depreciation

(55,016

)

Net unrealized appreciation

$

2,409,272

(a)

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.

(b)

When-issued security. Unsettled when-issued transactions were as follows:

Counterparty

Value

Unrealized
Appreciation

Merrill Lynch, Pierce, Fenner &
Smith, Inc.

$

998,856

$

7,443

(c)

Security represents a beneficial interest in a trust. The collateral deposited into the trust is federally tax-exempt revenue bonds issued by various state or local governments, or their respective agencies or authorities. The security is subject to remarketing prior to its stated maturity.

(d)

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

(e)

Securities represent bonds transferred to a TOB in exchange for which the Trust acquired residual interest certificates. These securities serve as collateral in a financing transaction.

(f)

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
August 31,
2011

Net
Activity

Shares
Held at
May 31, 2012

Income

FFI Institutional
Tax-Exempt
Fund

3,348,424

(2,700,212

)

648,212

$

—

(g)

Represents the current yield as of report date.

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)

EDC

Economic Development Corp.

GO

General Obligation Bonds

NPFGC

National Public Finance Guarantee Corp.

RB

Revenue Bonds

SO

Special Obligation

•

Financial futures contracts sold as of May 31, 2012 were as follows:

Contracts

Issue

Exchange

Expiration

Notional
Value

Unrealized
Depreciation

10

10-Year US
Treasury
Note

Chicago
Board of
Trade

September
2012

$

1,339,375

$

(11,738

)

•

For Trust compliance purposes, the Trust’s sector classifications refer to any one or more of the sector sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by Trust management. These definitions may not apply for purposes of this report, which may combine sector subclassifications for reporting ease.

•

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)

BLACKROCK MARYLAND MUNICIPAL BOND TRUST

MAY 31, 2012

3