-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PGDwo2fAJ1VT320WhL59KPfGlB/jGteU8EW1wJH/EJYUVikvb4eKNKMcLtEd8kxo
 dHQpA+WY5H1Tve0PPnMsxA==

<SEC-DOCUMENT>0001262067-06-000029.txt : 20060306
<SEC-HEADER>0001262067-06-000029.hdr.sgml : 20060306
<ACCEPTANCE-DATETIME>20060306184414
ACCESSION NUMBER:		0001262067-06-000029
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060303
FILED AS OF DATE:		20060306
DATE AS OF CHANGE:		20060306

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SYNOPSYS INC
		CENTRAL INDEX KEY:			0000883241
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				561546236
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1028

	BUSINESS ADDRESS:	
		STREET 1:		700 E MIDDLEFIELD RD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043-4033
		BUSINESS PHONE:		6509625000

	MAIL ADDRESS:	
		STREET 1:		700 E MIDDLEFIELD RD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043-4033

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CHAN CHI-FOON
		CENTRAL INDEX KEY:			0001249834

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19807
		FILM NUMBER:		06668380

	BUSINESS ADDRESS:	
		STREET 1:		SYNOPSYS INC
		STREET 2:		700 EAST MIDDLEFIELD RD.
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-03-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000883241</issuerCik>
        <issuerName>SYNOPSYS INC</issuerName>
        <issuerTradingSymbol>SNPS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001249834</rptOwnerCik>
            <rptOwnerName>CHAN CHI-FOON</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>700 EAST MIDDLEFIELD ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MOUNTAIN VIEW</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94043</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Pres &amp; COO, Actg Sr VP Mktg</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-03-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1678</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.0938</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>98321</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-03-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1678</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>22.4</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>96643</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>14.0938</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-03-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1678</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>1997-05-28</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2007-04-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1678</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27571</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Exercisable in 48 equal monthly installments beginning one month from grant date</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Stephen Buckhout pursuant to POA  For: Chi-Foon Chan</signatureName>
        <signatureDate>2006-03-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----