-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 kNz9c6W32GIyE4Vjhx8uOw==

<SEC-DOCUMENT>0000921895-08-000476.txt : 20080213
<SEC-HEADER>0000921895-08-000476.hdr.sgml : 20080213
<ACCEPTANCE-DATETIME>20080213193115
ACCESSION NUMBER:		0000921895-08-000476
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080207
FILED AS OF DATE:		20080213
DATE AS OF CHANGE:		20080213

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ADAPTEC INC
		CENTRAL INDEX KEY:			0000709804
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER COMMUNICATIONS EQUIPMENT [3576]
		IRS NUMBER:				942748530
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		691 S MILPITAS BLVD
		STREET 2:		M/S25
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
		BUSINESS PHONE:		4089458600

	MAIL ADDRESS:	
		STREET 1:		691 SOUTH MILPITAS BLVD
		STREET 2:		M/S25
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			QUICKE JOHN J
		CENTRAL INDEX KEY:			0001179588

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15071
		FILM NUMBER:		08607287

	BUSINESS ADDRESS:	
		STREET 1:		C/O SEQUA CORP
		STREET 2:		200 PARK AVENUE , 44TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10166
		BUSINESS PHONE:		2129865500X5210

	MAIL ADDRESS:	
		STREET 1:		C/O SEQUA CORP
		STREET 2:		200 PARK AVENUE, 44TH FL
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10166
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>qui52.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-02-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000709804</issuerCik>
        <issuerName>ADAPTEC INC</issuerName>
        <issuerTradingSymbol>ADPT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001179588</rptOwnerCik>
            <rptOwnerName>QUICKE JOHN J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O STEEL PARTNERS II L.P.</rptOwnerStreet1>
            <rptOwnerStreet2>590 MADISON AVENUE, 32ND FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>See Footnote No. 3</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.0010</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-02-07</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-12-13</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, $.001 Par Value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16250</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Appreciation Right</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.2800</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-02-07</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-12-13</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, $.001 Par Value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>32500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock Unit (&quot;RSU&quot;) granted pursuant to the Issuer's 2006 Director Plan.  The RSU covers 16,250 shares of common stock of the Issuer (the &quot;Shares&quot;).  Upon vesting, the Reporting Person is entitled to receive cash from the Issuer in an amount equal to 100% of the amount of the fair market value of the Shares multiplied by the number of Shares with respect to which the RSU shall have been vested.  The RSU vests with respect to 1/3 of the Shares underlying the RSU on December 13, 2008 and 1/12 of the Shares quarterly thereafter.  The Reporting Person has no rights as a shareholder with respect to any Shares by virtue of the holding of the RSU and would not become a shareholder upon settlement.</footnote>
        <footnote id="F2">The RSU expires upon the earliest of (a) the Reporting Person ceasing to be a member of the Board of Directors of the Issuer or (b) each vesting and the related cash settlement.</footnote>
        <footnote id="F3">The Reporting Person is also a member of a Section 13(d) group that owns more than 10% of the Issuer's outstanding common stock.</footnote>
        <footnote id="F4">Stock Appreciation Right (&quot;SAR&quot;) granted pursuant to the Issuer's 2006 Director Plan.  The SAR covers 32,500 Shares.  The SAR is exercisable, to the extent it has vested, at an exercise price equal to $3.28 per Share (the &quot;Exercise Price&quot;).  Upon exercise, the Reporting Person is entitled to receive cash from the Issuer in an amount equal to 100% of the amount by which the fair market value of the Shares on the date of exercise exceeds the Exercise Price multiplied by the number of Shares with respect to which the SAR shall have been exercised.  The SAR vests with respect to 1/3 of the Shares underlying the SAR on December 13, 2008 and 1/12 of the Shares quarterly thereafter.  The Reporting Person has no rights as a shareholder with respect to any Shares by virtue of the holding of the SAR and would not become a shareholder upon settlement.</footnote>
        <footnote id="F5">The SAR expires upon the earlier of (a) December 13, 2017, (b) three months after the Reporting Person ceases to be a member of the Board of Directors of the Issuer or (c) one year after the Reporting Person ceases to be a member of the Board of Directors of the Issuer due to the Reporting Person's death or disability.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Quicke, John J.</signatureName>
        <signatureDate>2008-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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