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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 BDFg35ecn7+bHQJEgitJcTWEtDPKWLzuU0vRIdj5g0IX7iUN0RM0e8nKzppQ8QNu
 eFWdkmIaF4/CaRNBhudUUw==

<SEC-DOCUMENT>0001005477-07-007856.txt : 20071108
<SEC-HEADER>0001005477-07-007856.hdr.sgml : 20071108
<ACCEPTANCE-DATETIME>20071108061554
ACCESSION NUMBER:		0001005477-07-007856
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20071101
FILED AS OF DATE:		20071108
DATE AS OF CHANGE:		20071108

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BLACKROCK INVESTMENT QUALITY MUNICIPAL TRUST INC
		CENTRAL INDEX KEY:			0000894242
		IRS NUMBER:				133690436
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		STREET 2:		MUTUAL FUND DEPARTMENT
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809
		BUSINESS PHONE:		888-825-2257

	MAIL ADDRESS:	
		STREET 1:		100 BELLEVUE PARKWAY
		STREET 2:		MUTUAL FUND DEPARTMENT
		CITY:			WILMINGTON
		STATE:			DE
		ZIP:			19809

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Harris Jerrold B
		CENTRAL INDEX KEY:			0001333739

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-07354
		FILM NUMBER:		071223359

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		212-810-5800

	MAIL ADDRESS:	
		STREET 1:		C/O BLACKROCK KELSO CAPITAL ADVISORS LLC
		STREET 2:		40 EAST 52ND STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar123.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2007-11-01</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000894242</issuerCik>
        <issuerName>BLACKROCK INVESTMENT QUALITY MUNICIPAL TRUST INC</issuerName>
        <issuerTradingSymbol>BKN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001333739</rptOwnerCik>
            <rptOwnerName>Harris Jerrold B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>40 EAST 52ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>/s/ Vincent B. Tritto, as Attorney-in-Fact</signatureName>
        <signatureDate>2007-11-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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