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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 VgLowKpWXYp6TDqRzq1PG7VbqWzBn+BVzZZ2QcOQm2e+jtmmbZw/VOF4Gj+dKmIC
 Jo53tkwaXQY/dSwlcnsPwQ==

<SEC-DOCUMENT>0001289430-10-000123.txt : 20101012
<SEC-HEADER>0001289430-10-000123.hdr.sgml : 20101011
<ACCEPTANCE-DATETIME>20101012172742
ACCESSION NUMBER:		0001289430-10-000123
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101008
FILED AS OF DATE:		20101012
DATE AS OF CHANGE:		20101012

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ATHEROS COMMUNICATIONS INC
		CENTRAL INDEX KEY:			0001140486
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				770485570
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5480 GREAT AMERICA PARKWAY
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054
		BUSINESS PHONE:		408-773-5200

	MAIL ADDRESS:	
		STREET 1:		5480 GREAT AMERICA PARKWAY
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95054

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HARRIS CHARLES E
		CENTRAL INDEX KEY:			0001017379

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50534
		FILM NUMBER:		101119996

	MAIL ADDRESS:	
		STREET 1:		1030N. ORANGE AVE
		STREET 2:		SUITE 300
		CITY:			ORLANDO
		STATE:			FL
		ZIP:			32801-1031
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-10-08</periodOfReport>

    <issuer>
        <issuerCik>0001140486</issuerCik>
        <issuerName>ATHEROS COMMUNICATIONS INC</issuerName>
        <issuerTradingSymbol>ATHR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001017379</rptOwnerCik>
            <rptOwnerName>HARRIS CHARLES E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ATHEROS COMMUNICATIONS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1700 TECHNOLOGY DRIVE</rptOwnerStreet2>
            <rptOwnerCity>SAN JOSE,</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.7006</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37435</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27.6868</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34935</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan.</footnote>
        <footnote id="F2">Represents the weighted average sales price for a number of sale transactions effected at prices ranging from $25.57 to $25.87.  The Reporting Person has provided to the issuer, and undertakes to provide upon request by the SEC staff, or any security holder of the issuer, information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F3">Represents the weighted average sales price for a number of sale transactions effected at prices ranging from $27.64 to $27.72.  The Reporting Person has provided to the issuer, and undertakes to provide upon request by the SEC staff, or any security holder of the issuer, information regarding the number of shares sold at each separate price within the range.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Bruce P. Johnson, Attorncy-in-fact</signatureName>
        <signatureDate>2010-10-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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