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:          811-07354          

          BlackRock Investment Quality Municipal Trust, Inc.          
(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 Investment Quality Municipal Trust, Inc.
                                        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:          October 31, 2006
Date of reporting period:         January 31, 2006

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
JANUARY 31, 2006 (unaudited)

BlackRock Investment Quality Municipal Trust (BKN)

             
Principal
           
Amount
      Option Call    
Rating1
(000)
   
Description
Provisions2  
Value
 
      LONG-TERM INVESTMENTS—147.9%      
        Alabama—5.8%      
AAA $14,000     Univ. of Alabama Hosp., Ser. A, 5.875%, 9/01/31, MBIA 09/10 @ 101   $   15,222,760  
             
 
        Arizona—1.9%      
AAA 2,895     Phoenix Civic Impvt. Corp., Civic Plaza Expansion Proj., 5.00%, 7/01/35, FGIC 7/15 @ 100   2,998,207  
        San. Luis Fac. Dev. Corp. Rev., Regl. Detention Ctr. Proj.,      
NR 490           6.25%, 5/01/15 05/10 @ 107   482,939  
NR 490           7.00%, 5/01/20 05/10 @ 107   480,871  
NR 980           7.25%, 5/01/27 05/10 @ 107   957,049  
             
 
              4,919,066  
             
 
        California—24.0%      
        California St., GO,      
AAA 10,000           5.00%, 3/01/33 03/15 @ 100   10,346,300  
A 2,625 3         5.625%, 5/01/18 N/A   2,878,811  
A 3,145           5.625%, 5/01/18 5/10 @ 101   3,421,729  
        Foothill/Eastn. Transp. Corridor Agcy.,      
BBB 7,000           Conv. Cap. Apprec., Zero Coupon, 1/15/28 01/14 @ 101   6,045,270  
BBB 3,495           Toll Road Rev., 5.75%, 1/15/40 01/10 @ 101   3,561,929  
A- 11,000     Golden St. Tobacco Sec. Corp., Ser. A, 5.00%, 6/01/45 06/15 @ 100   11,108,130  
AAA 10,945     Los Altos Sch. Dist., GO, Zero Coupon, 8/01/24, MBIA 08/13 @ 53.632   4,110,942  
AAA 4,750     Los Angeles Dept. of Wtr. & Pwr. Sys., 5.00%, 7/01/31, FSA 07/15 @ 100   4,960,805  
AAA 15,460     Los Angeles Cnty., Asset Leasing Corp. Rev. Proj., 5.95%, 12/01/07, AMBAC No Opt. Call   16,177,344  
              62,611,260  
             
 
        Colorado—0.8%      
Baa2 1,020     Park Creek Met. Dist. Rev., Ppty. Tax, 5.50%, 12/01/37 12/15 @ 101   1,050,528  
AAA 1,030     Springs Utils. Rev., Ser. C, 5.00%, 11/15/45, FSA 11/15 @ 100   1,058,006  
             
 
              2,108,534  
             
 
        Connecticut—1.2%      
Baa3 3,000     Mashantucket Western Pequot Tribe Spec. Rev., Ser. A, 5.50%, 9/01/28 09/09 @ 101   3,089,490  
             
 
        District of Columbia—2.2%      
BBB 4,960     Tobacco Settlement Fin. Corp., 6.50%, 5/15/33 No Opt. Call   5,626,872  
             
 
        Florida—17.0%      
AAA 5,705     Brd. of Ed. Pub. Ed., Cap. Outlay, GO, Ser. A, 5.00%, 6/01/31 06/14 @ 101   5,950,943  
NR 2,110     Fishhawk Cmnty. Dev. Dist. II, Spl. Assmt. Rev., Ser. A, 6.125%, 5/01/34 05/13 @ 101   2,209,508  
NR 3,700     Hillsborough Cnty. Ind. Dev. Auth., Nat. Gypsum Proj., Ser. A, 7.125%, 4/01/30 10/10 @ 101   4,047,652  
NR 2,250     Live Oak Cmnty. Dev. Dist. No. 2, Ser. A, 5.85%, 5/01/35 05/12 @ 101   2,282,625  
BB+ 4,755     Miami Beach Hlth. Facs. Auth., Mt. Sinai Med. Ctr. Proj., 6.75%, 11/15/21 11/14 @ 100   5,328,358  
        Miami Dade Cnty. Spl. Oblig. Cap. Apprec.,      
AAA 3,380           Ser. A, Zero Coupon, 10/01/31, MBIA 10/15 @ 44.051   908,476  
AAA 4,225           Ser. A, Zero Coupon, 10/01/32, MBIA 10/15 @ 41.782   1,076,065  
AAA 4,000           Ser. A, Zero Coupon, 10/01/33, MBIA 10/15 @ 39.621   964,240  
AAA 4,580           Ser. A, Zero Coupon, 10/01/34, MBIA 10/15 @ 37.635   1,048,728  
AAA 5,000           Ser. A, Zero Coupon, 10/01/35, MBIA 10/15 @ 35.678   1,085,400  
AAA 10,000           Ser. A, Zero Coupon, 10/01/36, MBIA 10/15 @ 33.817   2,055,600  
AAA 10,000           Ser. A, Zero Coupon, 10/01/37, MBIA 10/15 @ 32.047   1,947,900  
AAA 1,485     Peace River/Manasota Regl. Wtr. Sply. Auth., 5.00%, 10/01/30, FSA 10/15 @ 100   1,550,860  
AAA 3,785     Sumter Landing Cmnty. Dev. Dist., Ser B, 5.70%, 10/01/38 10/15 @ 100   3,800,367  
NR 9,975     Vlg. Cmnty. Dev. Dist. No. 6, Spl. Assmt. Rev., 5.625%, 5/01/22 05/13 @ 100   10,148,066  
             
 
              44,404,788  
             
 
        Georgia—4.2%      
AAA 5,000     Atlanta Arpt. Passenger Fac., Ser. J, 5.00%, 1/01/34, FSA 01/15 @ 100   5,144,650  
AAA 4,000     Atlanta Wtr. & Wstwtr., 5.00%, 11/01/34, FSA 11/14 @ 100   4,128,400  
BBB 1,500     Milledgeville Baldwin Cnty. Dev. Auth., Georgia Coll. & St. Univ. Fndtn. Proj., 6.00%, 9/01/33 09/14 @ 101   1,612,860  
             
 
              10,885,910  
             
 

1
BlackRock Investment Quality Municipal Trust (BKN) (continued)

             
Principal
           
Amount
      Option Call    
Rating1
(000)
   
Description
Provisions2  
Value
 
        Hawaii—1.0%      
AAA $ 2,500     Dept. of Budget & Fin., Hawaiian Elec. Co., Inc. Proj., Ser. D, 6.15%, 1/01/20, AMBAC 01/09 @ 101   $  2,694,250  
             
 
        Illinois—12.7%      
NR 1,920 4   Centerpoint Intermodal Ctr. Prog. Trust, Ser. A, 8.00%, 6/15/23 No Opt. Call   1,943,789  
AAA 1,040 3   Chicago Brd. of Ed. Sch. Reform, 5.75%, 12/01/07, AMBAC N/A   1,105,905  
AAA 5,000 5   Chicago Pub. Bldg., Ser. A, 7.00%, 1/01/20, MBIA ETM   6,431,250  
        Edl. Fac. Auth.,      
AAA 2,070           5.45%, 7/01/14, FGIC 03/06 @ 100   2,085,546  
AAA 2,575           5.70%, 7/01/13, FGIC 03/06 @ 100   2,597,454  
BB+ 690     Fin. Auth. Rev., Friendship Vlg. Schaumburg Proj., Ser. A, 5.625%, 2/15/37 02/15 @ 100   692,822  
        Fin. Auth. Student Hsg., MJH Ed. Asst. Living Proj.,      
Baa2 875           Ser. A, 5.125%, 6/01/35 06/14 @ 100   868,149  
Baa3 700           Ser. B, 5.375%, 6/01/35 06/14 @ 100   694,610  
AA+ 5,800     Fin. Auth., Northwestern Mem. Hosp. Proj., Ser. A, 5.50%, 8/15/43 08/14 @ 100   6,156,468  
        O’Hare Intl. Arpt.,      
AAA 1,000           Ser. A, 5.00%, 1/01/29, MBIA 01/15 @ 100   1,037,820  
AAA 1,610           Ser. A, 5.00%, 1/01/30, MBIA 01/15 @ 100   1,668,491  
AAA 4,055           Ser. A, 5.00%, 1/01/33, FGIC 01/16 @ 100   4,189,301  
AAA 3,540           Ser. C-2, 5.25%, 1/01/30, FSA 01/14 @ 100   3,671,971  
             
 
              33,143,576  
             
 
        Kentucky—2.7%      
AAA 15,715     Econ. Dev. Fin. Sys., Norton Hlth. Care, Inc. Proj., Ser. B, Zero Coupon, 10/01/23, MBIA No Opt. Call   6,954,045  
             
 
        Maine—0.9%      
AAA 2,150     Hlth. & Higher Edl. Fac. Auth., 5.00%, 7/01/29 07/15 @ 100   2,234,989  
             
 
        Maryland—0.7%      
BBB+ 1,740     Hlth. & Higher Edl. Facs. Auth., Medstar Hlth. Proj., 5.50%, 8/15/33 08/14 @ 100   1,796,132  
             
 
        Massachusetts—0.8%      
AAA 2,000     Wtr. Res. Auth., Ser. B, 5.00%, 8/01/35 08/17 @ 100   2,092,640  
             
 
        Multi-State—4.8%      
Baa1 7,000 4   Charter Mac Equity Issuer Trust, Ser. B, 7.60%, 11/30/50 11/10 @ 100   7,908,460  
Baa1 4,000 4   MuniMae TE Bond Subsidiary, LLC, Ser. B, 7.75%, 6/30/50 11/10 @ 100   4,502,160  
             
 
              12,410,620  
             
 
        New Jersey—4.2%      
AAA 2,000     Delaware River Port. Auth. of PA & NJ, Port Dist. Proj., Ser. B, 5.70%, 1/01/22, FSA 01/10 @ 100   2,152,640  
BBB 7,000     Econ. Dev. Auth. Cigarette Tax Rev., 5.75%, 6/15/29 06/14 @ 100   7,429,730  
NR 1,510     Middlesex Cnty. Imprt. Auth., Heldrich Ctr. Hotel Proj., Ser. B, 6.25%, 1/01/37 01/15 @ 100   1,493,858  
             
 
              11,076,228  
             
 
        New York—15.0%      
NR 725     Albany Indl. Dev. Agcy., New Covenant Charter Sch. Proj., Ser. A, 7.00%, 5/01/35 05/15 @ 102   685,256  
        Dorm. Auth.,      
AAA 1,865           Univ. of Rochester Proj., Ser. A, Zero Coupon, 7/01/21, MBIA 07/10 @ 101   1,594,071  
AAA 2,030           Univ. of Rochester Proj., Ser. A, Zero Coupon, 7/01/23, MBIA 07/10 @ 101   1,735,853  
AA- 19,820     Liberty Dev. Corp. Proj., 5.25%, 10/01/35 No Opt. Call   21,995,840  
        New York City, GO,      
A+ 4,805 5,6         Ser. E, 6.50%, 2/15/06 ETM   4,810,478  
A+ 2,195 6         Ser. E, 6.50%, 2/15/06 No Opt. Call   2,197,414  
BBB 8,825     New York Cntys. Tobacco Trust III, Zero Coupon, 6/01/38 06/15 @ 26.186   1,343,518  
        Sales Tax Asset Receivable Corp.,      
AAA 3,115           Ser. A, 5.00%, 10/15/29, AMBAC 10/14 @ 100   3,260,159  
AAA 1,500           Ser. A, 5.00%, 10/15/32, AMBAC 10/14 @ 100   1,563,270  
             
 
              39,185,859  
             
 
        North Carolina—3.0%      
AAA 5,000     Eastn. Mun. Pwr. Agcy. Sys. Rev., Ser. B, 7.00%, 1/01/08, CAPMAC No Opt. Call   5,338,750  
NR 2,425     Gaston Cnty. Indl. Facs. & Poll. Ctrl. Fin. Auth., 5.75%, 8/01/35 08/15 @ 100   2,543,849  
             
 
              7,882,599  
             
 

2

BlackRock Investment Quality Municipal Trust (BKN) (continued)
             
Principal
           
Amount
      Option Call    
Rating1
(000)
   
Description
Provisions2  
Value
 
        Ohio—7.8%      
AAA $10,475     Air Qual. Dev. Auth., 4.80%, 1/01/34, FGIC 07/15 @ 100   $  10,553,458  
        Cuyahoga Cnty. Cleveland Clinic Hlth. Sys. Proj.,      
Aa3 3,485           6.00%, 1/01/20 07/13 @ 100   3,911,459  
Aa3 5,000           6.00%, 1/01/21 07/13 @ 100   5,601,650  
AAA 290 5   Cuyahoga Cnty. Port Auth., Port Dev. Proj., 6.00%, 3/01/07 ETM   295,290  
             
 
              20,361,857  
             
 
        Oklahoma—1.2%      
B- 2,900     Tulsa Mun. Arpt. Trust, Ser. A, 7.75%, 6/01/35 No Opt. Call   3,058,572  
             
 
        Pennsylvania—7.4%      
        Econ. Dev. Fin. Auth.,      
A3 2,000           Amtrak Proj., Ser. A, 6.25%, 11/01/31 05/11 @ 101   2,132,180  
A3 3,100           Amtrak Proj., Ser. A, 6.375%, 11/01/41 05/11 @ 101   3,315,171  
BB- 8,235           Exempt Facs. Rev., Reliant Energy Conv. Proj., Ser. A, 6.75%, 12/01/36 12/09 @ 103   8,799,509  
AAA 4,000     Intergovtl. Coop. Auth., Spec. Tax, Philadelphia Fdg. Prog., 5.50%, 6/15/20, FGIC 06/06 @ 100   4,032,280  
        McKeesport Area Sch. Dist.,      
AAA 870 5         Zero Coupon, 10/01/31, FGIC ETM   260,174  
AAA 2,435           Zero Coupon, 10/01/31, FGIC No Opt. Call   694,316  
             
 
              19,233,630  
             
 
        Puerto Rico—1.9%      
BBB+ 4,825     Hwy. & Trans. Auth., 5.00%, 7/01/40 07/15 @ 100   4,871,706  
             
 
        Rhode Island—0.8%      
AAA 2,000     Hlth. & Edl. Bldg. Corp. Hosp. Fin., 5.50%, 5/15/16, MBIA 05/07 @ 102   2,078,640  
             
 
        South Carolina—2.7%      
        Jobs Econ. Dev. Auth. Hosp. Facs. Rev.,      
BBB+ 3,560 3         Palmetto Hlth. Proj., 6.875%, 8/01/27 N/A   4,250,177  
BBB+ 440           Palmetto Hlth. Proj., 6.875%, 8/01/27 08/13 @ 100   506,458  
BBB+ 2,185           Palmetto Hlth. Alliance Proj., Ser. A, 6.25%, 8/01/31 08/13 @ 100   2,363,886  
             
 
              7,120,521  
             
 
        Tennessee—2.0%      
AAA 4,865     Memphis Shelby Cnty. Arpt. Auth., Ser. D, 6.00%, 3/01/24, AMBAC 03/10 @ 101   5,219,561  
             
 
        Texas—13.5%      
BBB 4,300     Brazos River Auth., PCR, TXU Elec. Co. Proj., Ser. C, 6.75%, 10/01/38 10/13 @ 101   4,726,044  
AAA 6,000 3   Grapevine, GO, 5.875%, 8/15/10, FGIC N/A   6,603,060  
AAA 5,000     Harris Cnty. Houston Sports Auth., Ser. A, Zero Coupon, 11/15/38, MBIA 11/30 @ 61.166   822,450  
AAA 8,375     Humble Indpt. Sch. Dist., Sch. Bldg. Proj., Ser. B, 5.00%, 2/15/30, FGIC 02/15 @ 100   8,695,511  
AAA 9,495     La Joya Indpt. Sch. Dist., 5.00%, 2/15/34 02/14 @ 100   9,741,111  
AAA 15,000     Tpke. Auth. Central Sys. Rev., Zero Coupon, 8/15/31, AMBAC 08/12 @ 32.807   3,620,850  
AA+ 1,000     Wtr. Fin. Asst., GO, 5.75%, 8/01/22 08/10 @ 100   1,082,880  
             
 
              35,291,906  
             
 
        Utah—0.7%      
AAA 1,950 5   Intermountain Pwr. Agcy. Pwr. Sply. Rev., 5.00%, 7/01/13, AMBAC ETM   1,965,815  
             
 
        Washington—5.3%      
AAA 13,395     Pub. Pwr. Sply., Nuclear Proj. No. 1, 5.75%, 7/01/11, MBIA 07/06 @ 102   13,788,679  
             
 
        Wisconsin—1.7%      
A- 3,220     Hlth. & Edl. Facs. Auth., Aurora Hlth. Care Proj., 6.40%, 4/15/33 04/13 @ 100   3,550,823  
AAA 855     Pub. Pwr, Inc. Sys., Ser. A, 5.00%, 7/01/37, AMBAC 07/15 @ 100   882,830  
             
 
              4,433,653  
             
 
        Total Long-Term Investments (cost $365,619,039)     385,764,158  
             
 
        SHORT-TERM INVESTMENTS—8.2%      
        New York—1.9%      
A-1+ 5,000 7   City of New York, 3.12%, 2/01/06, FRWD N/A   5,000,000  
             
 
        Ohio—3.1%      
VMIG1 8,000 7   Hamilton Cnty. Hosp. Facs., Ser. A, 3.10%, 2/01/06, FRWD N/A   8,000,000  
             
 

3

BlackRock Investment Quality Municipal Trust (BKN) (continued)

             
           
Shares
           
 
(000)
   
Description
   
Value
 
        Money Market Fund—3.2%      
  8,400     AIM Tax Free Investment Co. Cash Reserve Portfolio     $  8,400,000  
             
 
        Total Short-Term Investments (cost $21,400,000)     21,400,000  
             
 
        Total Investments—156.1% (cost $387,019,0398)     407,164,158  
        Other assets in excess of liabilities—0.1%     373,562  
        Preferred shares at redemption value, including dividends payable—(56.2)%     (146,634,891 )
             
 
        Net Assets Applicable to Common Shareholders—100%     $ 260,902,829  
             
 

_______________  
1    Using the higher of Standard & Poor’s, Moody’s Investors Service or Fitch ratings.  
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    This bond is prerefunded. U.S. government securities, held in escrow, are used to pay interest on this security, as well as retire the bond in full at the date indicated, typically at a premium to par.  
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 January 31, 2006, the Trust held 5.5% of its net assets, with a current market value of $14,354,409, in securities restricted as to resale.  
5    Security is collateralized by U.S. Treasury obligations.  
6    Security, or a portion thereof, pledged as collateral with a value of $1,237,319 on 172 short U.S. Treasury Note futures contracts expiring March 2005 and 242 short U.S. Treasury Bond futures contracts expiring March 2005. The value of such contracts on January 31, 2006, was $45,959,438, with an unrealized gain of $43,485.  
7    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. Rate shown is rate as of January 31, 2006.  
8    Cost for Federal income tax purposes is $386,461,679. The net unrealized appreciation on a tax basis is $20,702,479, consisting of $21,209,410 gross unrealized appreciation and $506,931 gross unrealized depreciation.  
     
     

KEY TO ABBREVIATIONS

AMBAC   —   American Municipal Bond Assurance Corp.   FSA   —   Financial Security Assurance  
CAPMAC   —   Capital Markets Assurance Co.   GO   —   General Obligation  
FGIC   —   Financial Guaranty Insurance Co.   MBIA   —   Municipal Bond Insurance Assoc.  
FRWD   —   Floating Rate Weekly Demand   PCR   —   Pollution Control Revenue
 

4

Item 2. Controls and Procedures.
(a) The Registrant's principal executive and principal financial officers have evaluated the Registrant's disclosure controls and procedures within 90 days of this filing and have concluded, as of that date, that the Registrant’s disclosure controls and procedures were reasonably designed to ensure that information required to be disclosed by the Registrant in this Form N-Q was recorded, processed, summarized, and reported within the required time periods and that information to be disclosed by the Registrant in this Form N-Q was accumulated and communicated to the Registrant’s management , including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

(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 (17 CFR 270.30a -3(d)) 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.

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 Investment Quality Municipal Trust, Inc.     

By:      /s/ Henry Gabbay                                                                      
Name: Henry Gabbay
Title: Treasurer and Principal Financial Officer
Date: March 31, 2006

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: President and Principal Executive Officer
Date: March 31, 2006

By:      /s/ Henry Gabbay                                                                      
Name: Henry Gabbay
Title: Treasurer and Principal Financial Officer
Date: March 31, 2006