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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001179110-08-008423.txt : 20080429
<SEC-HEADER>0001179110-08-008423.hdr.sgml : 20080429
<ACCEPTANCE-DATETIME>20080429164724
ACCESSION NUMBER:		0001179110-08-008423
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080425
FILED AS OF DATE:		20080429
DATE AS OF CHANGE:		20080429

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CREDENCE SYSTEMS CORP
		CENTRAL INDEX KEY:			0000893162
		STANDARD INDUSTRIAL CLASSIFICATION:	INSTRUMENTS FOR MEAS & TESTING OF ELECTRICITY & ELEC SIGNALS [3825]
		IRS NUMBER:				942878499
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		1421 CALIFORNIA CIRCLE
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
		BUSINESS PHONE:		408635-4300

	MAIL ADDRESS:	
		STREET 1:		1421 CALIFORNIA CIRCLE
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hale Rance
		CENTRAL INDEX KEY:			0001382792

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22366
		FILM NUMBER:		08786232

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		(408) 635-4000

	MAIL ADDRESS:	
		STREET 1:		C/O CREDENCE SYSTEMS CORPORATION
		STREET 2:		1421 CALIFORNIA STREET
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
</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>2008-04-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000893162</issuerCik>
        <issuerName>CREDENCE SYSTEMS CORP</issuerName>
        <issuerTradingSymbol>CMOS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001382792</rptOwnerCik>
            <rptOwnerName>Hale Rance</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>CREDENCE SYSTEMS CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>1421 CALIFORNIA CIRCLE</rptOwnerStreet2>
            <rptOwnerCity>MILPITAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95035</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP Manufacturing Ops</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>350000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>376488</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock Unit award granted on 4/25/08 with 100% of the units vesting upon completion of four (4) years of service measured from the grant date.  Vesting will be accelerated on the units granted if the Company meets certain performance criteria or upon the occurrence of certain events in connection with a change of control.</footnote>
        <footnote id="F2">In addition to the 350,000 restricted stock units, 25,000 shares are subject to a restricted stock award dated 5/30/06 which vests annually over a period of three years, with 5,321 shares remaining from the first vest period of the restrictred award and 4,500 shares purchased through the Company's Employee Stock Purchase Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Byron Milstead for Rance Hale</signatureName>
        <signatureDate>2008-04-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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