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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Udf2z/Rodkk7Wjt/r1TZtx/BWhtqBxaSoGdy20eG/6LauyY22EPME0tntblwO1bT
 tgL63yNTIPubcY11QIiIUA==

<SEC-DOCUMENT>0001179110-07-011650.txt : 20070530
<SEC-HEADER>0001179110-07-011650.hdr.sgml : 20070530
<ACCEPTANCE-DATETIME>20070530174048
ACCESSION NUMBER:		0001179110-07-011650
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070105
FILED AS OF DATE:		20070530
DATE AS OF CHANGE:		20070530

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CERUS CORP
		CENTRAL INDEX KEY:			0001020214
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				680262011
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2411 STANWELL DR
		CITY:			CONCORD
		STATE:			CA
		ZIP:			94520
		BUSINESS PHONE:		9252886000

	MAIL ADDRESS:	
		STREET 1:		2525 STANWELL DRIVE
		STREET 2:		STE 300
		CITY:			CONCORD
		STATE:			CA
		ZIP:			94520

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CERUS TECHNOLOGIES INC
		DATE OF NAME CHANGE:	19960731

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Greenman William Mariner
		CENTRAL INDEX KEY:			0001377258

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21937
		FILM NUMBER:		07888639

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		(925) 288-6000

	MAIL ADDRESS:	
		STREET 1:		C/O CERUS CORPORATION
		STREET 2:		2411 STANWELL DRIVE
		CITY:			CONCORD
		STATE:			CA
		ZIP:			94520
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4/A -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2007-01-05</periodOfReport>

    <dateOfOriginalSubmission>2007-01-09</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001020214</issuerCik>
        <issuerName>CERUS CORP</issuerName>
        <issuerTradingSymbol>CERS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001377258</rptOwnerCik>
            <rptOwnerName>Greenman William Mariner</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CERUS CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>2411 STANWELL DRIVE</rptOwnerStreet2>
            <rptOwnerCity>CONCORD</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94520</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, Cerus Europe</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-01-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4958</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>80984</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Not applicable.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>William M. Greenman by Howard G. Ervin, attorney-in-fact</signatureName>
        <signatureDate>2007-05-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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