-----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,
 Mz+938q77eWAs2hNtEBMqSnGDhSb2ssGRvF0BSKI242sPPimJbIBJp7UF5b0jmvO
 sia3QhBRWIEQiIx8f6iE4g==

<SEC-DOCUMENT>0000849778-06-000006.txt : 20060809
<SEC-HEADER>0000849778-06-000006.hdr.sgml : 20060809
<ACCEPTANCE-DATETIME>20060809092539
ACCESSION NUMBER:		0000849778-06-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060808
FILED AS OF DATE:		20060809
DATE AS OF CHANGE:		20060809

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CYTYC CORP
		CENTRAL INDEX KEY:			0000849778
		STANDARD INDUSTRIAL CLASSIFICATION:	LABORATORY ANALYTICAL INSTRUMENTS [3826]
		IRS NUMBER:				020407755
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		250 CAMPUS DRIVE
		CITY:			MALBOROUGH
		STATE:			MA
		ZIP:			01752
		BUSINESS PHONE:		5082638495

	MAIL ADDRESS:	
		STREET 1:		250 CAMPUS DRIVE
		CITY:			MALBOROUGH
		STATE:			MA
		ZIP:			01752

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SULLIVAN PATRICK J
		CENTRAL INDEX KEY:			0001039138
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-27558
		FILM NUMBER:		061015300

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		9782638000

	MAIL ADDRESS:	
		STREET 1:		85 SWANSON ROAD
		STREET 2:		.
		CITY:			BOXBOROUGH
		STATE:			MA
		ZIP:			01719
</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>2006-08-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000849778</issuerCik>
        <issuerName>CYTYC CORP</issuerName>
        <issuerTradingSymbol>CYTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001039138</rptOwnerCik>
            <rptOwnerName>SULLIVAN PATRICK J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>250 CAMPUS DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MARLBOROUGH</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01752</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2006-08-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>30000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.4672</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>255544</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sale reported on this Form 4 was made pursuant to a written trading plan adopted in accordance with SEC Rule 10b5-1 on July 28, 2006.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Phyllis C. Howard, Attorney-in-Fact  For: Patrick J. Sullivan</signatureName>
        <signatureDate>2006-08-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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