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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,
 K7BEwEKE7tUK91c5O+pqQaC/psMgqmCYwySDXGuvwRaUy0iUU3zByJG3zqV7SmCq
 /ugXhdZPNbXTs7/uog0cFQ==

<SEC-DOCUMENT>0001179110-06-003091.txt : 20060208
<SEC-HEADER>0001179110-06-003091.hdr.sgml : 20060208
<ACCEPTANCE-DATETIME>20060208115434
ACCESSION NUMBER:		0001179110-06-003091
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060206
FILED AS OF DATE:		20060208
DATE AS OF CHANGE:		20060208

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INTERNATIONAL BANCSHARES CORP
		CENTRAL INDEX KEY:			0000315709
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				742157138
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		12OO SAN BERNARDO AVE
		STREET 2:		PO BOX 1359
		CITY:			LAREDO
		STATE:			TX
		ZIP:			78040-1359
		BUSINESS PHONE:		9567227611

	MAIL ADDRESS:	
		STREET 1:		P O BOX 1359
		STREET 2:		1200 SAN BERNARDO
		CITY:			LAREDO
		STATE:			TX
		ZIP:			78040

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SANCHEZ ANTONIO R JR
		CENTRAL INDEX KEY:			0001060529

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-09439
		FILM NUMBER:		06587800

	BUSINESS ADDRESS:	
		STREET 1:		PO BOX 2986
		CITY:			LORDO
		STATE:			TX
		ZIP:			78044
		BUSINESS PHONE:		9567228092

	MAIL ADDRESS:	
		STREET 1:		P.O. BOX 2986
		CITY:			LAREDO
		STATE:			TX
		ZIP:			78044
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-02-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000315709</issuerCik>
        <issuerName>INTERNATIONAL BANCSHARES CORP</issuerName>
        <issuerTradingSymbol>IBOC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001060529</rptOwnerCik>
            <rptOwnerName>SANCHEZ ANTONIO R JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P.O. BOX 2986</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAREDO</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78044</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2006-02-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>202755</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27.7742</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4406052</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>BY TRUST</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2447464</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>BY PARTNERSHIP</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2681420</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person disclaims beneficial ownership of the reported securities except to the extent of his pecuniary interest therein, if any.</footnote>
        <footnote id="F2">As of December 22, 2005, the reporting person ceased to be co-trustee of certain trusts which in the aggregate hold 350,042 shares for the benefit of the reporitng person's niece and nephew, and therefore, shares held by such trusts are no longer included in the number of shares being reported as beneficially owned by the reporting person.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/S/ANTONIO R. SANCHEZ JR.</signatureName>
        <signatureDate>2006-02-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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