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:__811-21036______

_______BlackRock Municipal Bond Trust_______
(Exact name of registrant as specified in charter)

100 Bellevue Parkway, Wilmington, DE    19809 
(Address of principal executive offices) 
 
(Zip code) 

Robert S. Kapito, President

BlackRock Municipal Bond Trust

_______40 East 52nd Street, New York, NY 10022_______
(Name and address of agent for service)

Registrant's telephone number, including area code:_888-825-2257__________________

Date of fiscal year end:___August 31, 2005

Date of reporting period:__May 31, 2005_________________________________

Item 1. Schedule of Investments.

The registrant’s unaudited schedule of investments as of the close of the reporting period pursuant to Rule 30b1-5 under the Investment Company Act of 1940 is as follows:


PORTFOLIO OF INVESTMENTS
MAY 31, 2005 (Unaudited)
BlackRock Municipal Bond Trust (BBK)

 
Principal
 
 
Amount
Option Call
 
 
Rating1
(000)
Description
Provisions2
Value
 
        LONG-TERM INVESTMENTS—151.5%        
          Alabama—10.8%        
  BBB   $ 9,250   Courtland Ind. Dev. Brd., PCR, Champion Intl. Corp. Proj., Ser. A, 6.50%, 9/01/25   09/05 @ 102   $ 9,517,232  
  A2   7,500   Huntsville Hlth. Care Auth., Ser. A, 5.75%, 6/01/31   06/11 @ 101   7,988,250  
                  17,505,482  
          California—15.2%        
  AA+   765   Edl. Fac. Auth., Univ. So. California, Ser. A, 5.00%, 10/01/33   04/13 @ 100   803,862  
          Golden St. Tobacco Sec. Corp., Ser. B,        
  A-   7,300      5.50%, 6/01/43   06/13 @ 100   7,816,986  
  A-   4,200      5.625%, 6/01/38   06/13 @ 100   4,576,782  
  B-   8,000   Los Angeles Regl. Arpt. Impvt., Corp. Lease Rev., Amer. Airlines, Inc. Proj., Ser. B,        
             7.50%, 12/01/24   12/12 @ 102   8,401,280  
          San Marcos Spl. Tax, Cmnty. Facs. Dist. No. 02-01,        
  NR   465      5.90%, 9/01/28   09/10 @ 102   475,946  
  NR   865      5.95%, 9/01/35   09/10 @ 102   885,838  
  NR   1,585   Val Verde Unified Sch. Dist. Fin. Auth., Spec. Tax Rev., 6.25%, 10/01/28   10/13 @ 102   1,672,460  
                  24,633,154  
          District of Columbia—11.1%        
          Dist. of Columbia,   
  A   595      Friendship Pub. Charter Sch., Inc., 5.25%, 6/01/33, ACA   06/14 @ 100   614,373  
  AAA   6,000      Gallary Place Proj., 5.40%, 7/01/31, FSA   07/12 @ 100   6,436,680  
  AAA   33,450      Georgetown Univ., Ser. A, Zero Coupon, 4/01/38, MBIA   04/11 @ 20.243   5,031,883  
  BBB   5,580      Tobacco Settlement Fin. Corp., 6.75%, 5/15/40   05/11 @ 101   5,992,474  
                  18,075,410  
          Florida—21.4%        
  AAA   3,455   Brd. of Ed. Pub. Ed., Cap. Outlay, Ser. A, 5.00%, 6/01/31   06/14 @ 101   3,678,711  
  BBB-   6,200   Martin Cnty. Indl. Dev. Auth., Indiantown Cogeneration Proj., Ser. A, 7.875%, 12/15/25   07/05 @ 102   6,376,700  
  BB+   2,810   Miami Beach Hlth. Facs. Auth., Mt. Sinai Med. Ctr. Proj., 6.75%, 11/15/21   11/14 @ 100   3,178,700  
  A   10,000   Orange Cnty. Hlth. Facs. Auth., Hosp. Adventist Hlth. Sys. Proj., 5.625%, 11/15/32   11/12 @ 101   10,770,400  
  AAA   7,255   Palm Beach Cnty. Hsg. Fin. Auth., Multi-Fam. Rev., Indian Trace Apts., Ser. A,        
             5.625%, 1/01/44, FSA   01/12 @ 100   7,522,637  
  NR   605   Pine Islands Cmnty. Dev. Dist., Spl. Assmt., 5.75%, 5/01/35   05/12 @ 101   619,841  
  NR   1,470   Reunion West Cmnty. Dev. Dist., Spl. Assmt., 6.25%, 5/01/36   05/12 @ 101   1,550,674  
  NR   1,000   Stevens Plantation Cmnty. Dev. Dist., Spl. Assmt. Rev., Ser. A, 7.10%, 5/01/35   05/14 @ 100   1,040,270  
                  34,737,933  
          Georgia—8.4%        
          Atlanta Arpt. Passenger Fac., FSA,        
  AAA   5,000      Ser. C, 5.00%, 1/01/33   07/14 @ 100   5,229,950  
  AAA   3,000      Ser. J, 5.00%, 1/01/34   01/15 @ 100   3,136,950  
  AAA   5,000   Atlanta Wtr. & Wstwtr., 5.00%, 11/01/37, FSA   11/14 @ 100   5,284,250  
                  13,651,150  
          Illinois—20.8%        
  AAA   23,065   Bolingbrook, GO, Ser. B, Zero Coupon, 1/01/36, FGIC   01/12 @ 23.018   3,824,408  
  NR   1,150   Centerpoint Intermodal Ctr. Prog. Trust, Ser. A, 8.00%, 6/15/23   No Opt. Call   1,180,406  
  AAA   5,8803   Chicago, GO, Ser. A, 5.50%, 1/01/38, MBIA   01/11 @ 101   6,444,303  
  Baa2   6,000   Edl. Facs. Auth., Student Hsg. Rev., Edl. Advancement Fund Univ. Ctr. Proj., 6.25%, 5/01/34   05/07 @ 100   6,215,520  
          Fin. Auth. Student Hsg., MJH Ed. Asst. IV Proj.,        
  Baa2   525      Ser. A, 5.125%, 6/01/35   06/14 @ 100   527,814  
  Baa3   425      Ser. B, 5.375%, 6/01/35   06/14 @ 100   427,257  
  A   6,000   Hlth. Facs. Auth., Lake Forest Hosp., Ser. A, 5.75%, 7/01/29   07/12 @ 100   6,309,000  
          Met. Pier & Exposition Auth., Ded. St. Tax Rev., McCormick Place Expansion Proj., Ser. A, MBIA,   
  AAA   10,000      Zero Coupon, 6/15/35   No Opt. Call   2,413,200  
  AAA   10,000      Zero Coupon, 12/15/36   No Opt. Call   2,240,900  
  AAA   10,000      Zero Coupon, 12/15/37   No Opt. Call   2,130,300  
          O’Hare Intl. Arpt., Ser. A, MBIA,        
  AAA   1,000      5.00%, 1/01/29   01/15 @ 100   1,049,640  
  AAA   1,000      5.00%, 1/01/30   01/15 @ 100   1,048,040  
                  33,810,788  

1

BlackRock Municipal Bond Trust (BBK) (continued)

 
Principal
 
Amount
Option Call
 
Rating1
(000)
Description
Provisions2
Value
        Indiana—1.3%        
  Aa2   $ 2,000   Multi-Fam. Hsg., Canterbury House Apts., Ser. 1, 5.90%, 12/01/34   12/11 @ 100   $ 2,110,660  
          Kansas—3.3%        
  A-   5,000   Wichita Arpt. Auth., Arpt. Facs. Rev., Cessna Citation Svc. Ctr., Ser. A, 6.25%, 6/15/32   06/12 @ 101   5,423,650  
          Louisiana—0.7%        
  Baa1   1,165   Local Gov’t. Env. Facs. & Cmnty. Dev. Auth., Oakleigh Apts. Proj., Ser. A, 6.375%, 6/01/38   06/13 @ 102   1,199,065  
          Maryland—3.4%        
  NR   1,250   Baltimore, Spec. Oblig. Rev., Harborview Lot No. 2 Proj., 6.50%, 7/01/31   07/13 @ 101   1,326,925  
  NR   3,000   Frederick Cnty. Spl. Oblig., Urbana Cmnty. Dev. Auth., Ser. B, 6.25%, 7/01/30   07/07 @ 102   3,037,470  
  Baa1   1,040   Hlth. & Higher Edl. Facs. Auth., Medstar Hlth. Proj., 5.50%, 8/15/33   08/14 @ 100   1,086,467  
                  5,450,862  
          Massachusetts—2.1%        
  AAA   2,200   Hlth. & Edl. Fac. Auth., Harvard Univ., Ser. A, 5.00%, 7/15/36   07/15 @ 100   2,349,358  
  AAA   1,000   Tpke. Auth., Met. Hwy. Sys. Rev., Ser. A, 5.00%, 1/01/37, MBIA   01/07 @ 102   1,034,010  
                  3,383,368  
          Michigan—0.7%        
  AAA   1,000   Detroit Sewage Disp., Second Lien, Ser. A, 5.00%, 7/01/35, MBIA   07/15 @ 100   1,062,610  
          Multi-State—7.4%        
  Baa1   10,5004   Charter Mac Equity Issuer Trust, Ser. B-2, 7.20%, 10/31/14   10/14@ 100   11,996,145  
          Nebraska—0.4%        
  Aa2   615   Univ. Nebraska, Univ. Revs., Lincoln Student Fees & Facs., Ser. B, 5.00%, 7/01/33   11/13 @ 100   646,199  
          Nevada—1.1%        
  NR   290   Director of the Dept. of Business & Ind., Las Ventanas Retirement Proj., Ser. A, 7.00%, 11/15/34   11/14 @ 100   300,208  
  NR   1,400   Las Vegas Spec. Impvt. Dist. No. 809, Summerlin Area, 5.65%, 6/01/23   12/05 @ 103   1,429,890  
                  1,730,098  
          New Jersey—9.7%        
          Econ. Dev. Auth.,        
  BBB   1,500      Cigarette Tax Rev., 5.50%, 6/15/31   06/14 @ 100   1,569,855  
  B   3,000      Continental Airlines, Inc. Proj., 7.20%, 11/15/30   11/10 @ 101   2,785,110  
  Baa3   7,500      Kapkowski Rd. Landfill Proj., 6.50%, 4/01/28   No Opt. Call   8,853,225  
  BBB-   1,500      Winchester Proj., Ser. A, 5.80%, 11/01/31   11/14 @ 100   1,575,030  
  NR   915      Middlesex Cnty. Imprvt. Auth., Heldrich Ctr. Hotel Proj., Ser. B, 6.25%, 1/01/37   01/15 @ 100   912,658  
                  15,695,878  
          New York—4.3%        
  AAA   1,330   Env. Facs. Corp., Clean Wtr. & Drinking Wtr. Rev., NYC Mun. Wtr. Proj., Ser. B,        
             5.00%, 6/15/31   06/12 @ 100   1,394,199  
  AAA   1,760   Met. Transp. Auth., Svc. Contract, Ser. A, 5.00%, 7/01/30, AMBAC   07/12 @ 100   1,846,487  
          New York City Mun. Wtr. Fin. Auth., Wtr. & Swr. Sys. Rev.,      
  AAA   570      Ser. A, 5.00%, 6/15/35, MBIA   06/13 @ 100   600,016  
  AA+   1,050      Ser. D, 5.00%, 6/15/38   06/15 @ 100   1,110,249  
  AAA   1,885   Sales Tax Asset Receivable Corp., Ser. A, 5.00%, 10/15/29, AMBAC   10/14 @ 100   2,021,832  
                  6,972,783  
          Ohio—1.0%        
  NR   1,500   Port Greater Cincinnati Dev. Auth., Cooperative Pub. Pkg. Infrastructure Proj., 6.40%, 2/15/34   02/14 @ 102   1,597,935  
          Oklahoma—1.1%        
  B-   1,725   Tulsa Mun. Arpt. Trust, Ser. A, 7.75%, 6/01/35   No Opt. Call   1,784,168  
          Oregon—0.6%        
  Aa2   995   Multi-Fam. Hsg., Pacific Tower Apts., Ser. 6, 6.05%, 11/01/34   12/11 @ 100   1,050,382  
          Pennsylvania—3.2%        
  BB-   4,895   Econ. Dev. Fin. Auth., Exempt Facs. Rev., Reliant Energy Conv. Proj., Ser. A, 6.75%, 12/01/36   12/09 @ 103   5,253,999  
          South Carolina—0.7%        
  BBB+   1,000   Jobs Econ. Dev. Auth., Hosp. Facs. Rev., Palmetto Hlth. Alliance Proj., Ser. C, 7.00%, 8/01/30   08/13 @ 100   1,150,670  
          Texas—16.0%        
  BBB   880   Brazos River Auth., PCR, TXU Elec. Co. Proj., Ser. C, 6.75%, 10/01/38   10/13 @ 101   982,934  
  AAA   940   Dallas Area Rapid Trans., 5.00%, 12/01/31, AMBAC   12/11 @ 100   977,478  
  AAA   715   Harlandale Indpt. Sch. Dist., Refdg., 5.00%, 8/15/35   08/15 @ 100   749,306  
  AAA   11,690   Harris Cnty. Houston Sports Auth., Ser. G, Zero Coupon, 11/15/41, MBIA   11/31 @ 53.779   1,659,279  
  AAA   550   Lake Dallas Indpt. Sch. Dist., Refdg. Sch. Bldg., 5.00%, 8/15/37   08/14 @ 100   576,405  
  Aa2   2,840   Multi-Fam. Hsg., Copperwood Ranch Apts., Ser. 9, 5.95%, 11/01/35   12/11 @ 100   2,998,103

2

BlackRock Municipal Bond Trust (BBK) (continued)

 
Principal
 
Rating1
Amount
Option Call
 
(000)
Description
Provisions2
Value
        Texas (continued)        
  AAA   $60,000   Tpke. Auth., Central Sys. Rev., Zero Coupon, 8/15/35, AMBAC   08/12 @ 25.665   $ 10,826,400  
  BBB+   6,840   Tyler Cnty. Hlth. Facs. Dev., Mother Frances Hosp., 6.00%, 7/01/31   07/12 @ 100   7,239,045  
                  26,008,950  
          Virginia—0.9%        
  B   1,500   Hopewell Indl. Dev. Auth. Env. Impvt. Rev., Refdg. Smurfit Stone Container, 5.25%, 6/01/15   No Opt. Call   1,513,335  
          West Virginia—0.3%        
  AAA   520   Econ. Dev. Auth., Correctional Juvenile Safety, Ser. A, 5.00%, 6/01/29, MBIA   06/14 @ 100   550,893  
          Wisconsin—5.6%        
          Hlth. & Edl. Facs. Auth.,        
  A-   1,350      Aurora Hlth. Care Proj., 6.40%, 4/15/33   04/13 @ 100   1,505,020  
  A   7,000      Wheaton Franciscan Svcs., 5.75%, 8/15/30   02/12 @ 101   7,510,720  
                  9,015,740  
          Total Long-Term Investments (cost $227,347,604)       246,011,307  
          SHORT-TERM INVESTMENTS—3.2%        
          California—0.4%        
  A1+   6105   Orange Cnty. Sanitation Dist., COP, Ser. A, 2.93%, 6/01/05, FRDD   N/A   610,000  
          New York—0.4%        
  A1+   7005   New York City Transl. Fin. Auth., Ser. A-1, 3.03%, 6/01/05, FRWD   N/A   700,000  
          Ohio—2.4%        
  VMIG1   1,4855   Hamilton Cnty. Hosp. Facs., 3.01%, 6/02/05, FRWD   N/A   1,485,000  
  VMIG1   2,4005   Univ. of Akron, 2.96%, 6/02/05, FGIC, FRWD   N/A   2,400,000  
                  3,885,000  
          Total Short-Term Investments (cost $5,195,000)       5,195,000  
          Total Investments—154.7% (cost $232,542,6046)       $251,206,307  
          Other assets in excess of liabilities—1.1%       1,688,378  
          Preferred shares at redemption value, including dividends payable—(55.8)%       (90,534,783)  
          Net Assets Applicable to Common Shareholders—100%       $162,359,902  
1   Using the higher of S&P’s, Moody’s or Fitch’s rating.  
2   Date (month/year) and price of the earliest optional call or redemption. There may be other call provisions at varying prices at later dates.  
3   Securities, or a portion thereof, pledged as collateral with a value of $2,191,940 on 793 short U.S. Treasury Note futures contracts expiring Sept. 2005. The value of such contracts on May 31, 2005 was $89,819,641, with an unrealized loss of $987,311.  
4   Security is not registered under the Securities Act of 1933. These securities may be resold in transactions in accordance with Rule 144A under that Act, to qualified institutional buyers. As of May 31, 2005, the Trust held 7.4% of it nets assets, with a current market value of $11,996,145, in securities restricted as to resale.  
5   For purposes of amortized cost valuation, the maturity date of this instrument is considered to be the earlier of the next date on which the security can be redeemed at par, or the next date on which the rate of interest is adjusted.  
6   Cost for Federal income purposes is $232,530,381. The net unrealized appreciation on a tax basis is $18,675,926 consisting of $18,675,926 gross unrealized appreciation and $0 gross unrealized depreciation. 
 
KEY TO ABBREVIATIONS
ACA   — American Capital Access   FSA   — Financial Security Assurance  
AMBAC   — American Municipal Bond Assurance Corporation   GO   — General Obligation  
FGIC   — Financial Guaranty Insurance Company   MBIA   — Municipal Bond Insurance Association  
FRDD   — Floating Rate Daily Demand   PCR   — Pollution Control Revenue  
FRWD   — Floating Rate Weekly Demand      

3

Item 2. Controls and Procedures.

(a) The registrant's principal executive officer and principal financial officer have evaluated the registrant's disclosure controls and procedures within 90 days of this filing and have concluded that the registrant’s disclosure controls and procedures are effective, as of that date, in ensuring that information required to be disclosed by the registrant in this Form N-Q was recorded, processed, summarized, and reported timely.

(b) The registrant's principal executive officer and principal financial officer are aware of no changes in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting.

Item 3. Exhibits.

Separate certifications of the registrant’s principal executive and financial officers pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 are attached as EX-99.CERT.

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.

(Registrant)___BlackRock Municipal Bond Trust___

By: __/s/ Henry Gabbay_____________________________________________
Name: Henry Gabbay
Title: Treasurer
Date: July 22, 2005

      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/ Robert S. Kapito_____________________________________________
Name: Robert S. Kapito
Title: Principal Executive Officer
Date: July 22, 2005

By: __/s/ Henry Gabbay_____________________________________________
Name: Henry Gabbay
Title: Principal Financial Officer
Date: July 22, 2005