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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 RR0h/E04hEuI4gxGi2rirDlN3FCgTDRI1Zkd5SHLNAWQqKHnABDATlSEV9DdRoVt
 PhLiKiRcnzWCdGFyOYjUWw==

<SEC-DOCUMENT>0001298256-04-000032.txt : 20041022
<SEC-HEADER>0001298256-04-000032.hdr.sgml : 20041022
<ACCEPTANCE-DATETIME>20041022170836
ACCESSION NUMBER:		0001298256-04-000032
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041021
FILED AS OF DATE:		20041022
DATE AS OF CHANGE:		20041022

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KAPITO ROBERT
		CENTRAL INDEX KEY:			0001059246

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-07354
		FILM NUMBER:		041092437

	BUSINESS ADDRESS:	
		STREET 1:		C/O BLACKROCK FINANCIAL MANAGEMENT INC.
		STREET 2:		40 EAST 52ND STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	MAIL ADDRESS:	
		STREET 1:		C/O BLACKROCK FINANCIAL MANAGEMENT INC.
		STREET 2:		40 EAST 52ND STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

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:		302-797-2449
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-10-21</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001059246</rptOwnerCik>
            <rptOwnerName>KAPITO ROBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O BLACKROCK FINANCIAL MANAGEMENT, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>40 EAST 52ND STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle>President &amp; CEO of the Trust</officerTitle>
            <otherText>Vice Chairman of Inv. Adviser</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Shares of Common Stock (par value $0.001 per share)</value>
            </securityTitle>
            <transactionDate>
                <value>2004-10-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.9158</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10110</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Bartholomew Battista</signatureName>
        <signatureDate>2004-10-22</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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