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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 SONVPXVXhdO2mQSLu+3ojzQAywgEKICVvEfUiHw3OWWlbuxI9eydgKNBKog428dM
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<SEC-DOCUMENT>0001181431-04-057898.txt : 20041210
<SEC-HEADER>0001181431-04-057898.hdr.sgml : 20041210
<ACCEPTANCE-DATETIME>20041210125138
ACCESSION NUMBER:		0001181431-04-057898
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041208
FILED AS OF DATE:		20041210
DATE AS OF CHANGE:		20041210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ANSYS INC
		CENTRAL INDEX KEY:			0001013462
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				043219960
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		275 TECHNOLOGY DRIVE, SOUTHPOINTE
		CITY:			CANONSBURG
		STATE:			PA
		ZIP:			15317
		BUSINESS PHONE:		4127643304

	MAIL ADDRESS:	
		STREET 1:		275 TECHNOLOGY DRIVE, SOUTHPOINTE
		CITY:			CANONSBURG
		STATE:			PA
		ZIP:			15317

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ZILVITIS PATRICK J
		CENTRAL INDEX KEY:			0001199455

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20853
		FILM NUMBER:		041195399

	MAIL ADDRESS:	
		STREET 1:		275 TECHNOLOGY DRIVE
		CITY:			CONONSBURG
		STATE:			PA
		ZIP:			15317
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd60726.xml
<DESCRIPTION>STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-12-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001013462</issuerCik>
        <issuerName>ANSYS INC</issuerName>
        <issuerTradingSymbol>ANSS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001199455</rptOwnerCik>
            <rptOwnerName>ZILVITIS PATRICK J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SOUTHPOINTE</rptOwnerStreet1>
            <rptOwnerStreet2>275 TECHNOLOGY DRIVE</rptOwnerStreet2>
            <rptOwnerCity>CANONSBURG</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>15317</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-12-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>32.2846</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <remarks>Shares and stock price reflect 2 for 1 stock split that occurred on 10/4/04</remarks>

    <ownerSignature>
        <signatureName>Lisa M. O'Connor, attorney-in-fact</signatureName>
        <signatureDate>2004-12-10</signatureDate>
    </ownerSignature>
</ownershipDocument>

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