<SUBMISSION>
<ACCESSION-NUMBER>0000949297-09-000036
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090508
<FILING-DATE>20090512
<DATE-OF-FILING-DATE-CHANGE>20090512
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Di Bari Arthur
<CIK>0001430103
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-26786
<FILM-NUMBER>09817581
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>C/O APAC CUSTOMER SERVICES, INC.
<STREET2>SIX PARKWAY NORTH
<CITY>DEERFIELD
<STATE>IL
<ZIP>60015
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>APAC CUSTOMER SERVICE INC
<CIK>0000949297
<ASSIGNED-SIC>7389
<IRS-NUMBER>362777140
<STATE-OF-INCORPORATION>IL
<FISCAL-YEAR-END>1230
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>SIX PARKWAY NORTH
<CITY>DEERFIELD
<STATE>IL
<ZIP>60015
<PHONE>847-236-5452
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>SIX PARKWAY NORTH
<CITY>DEERFIELD
<STATE>IL
<ZIP>60015
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>APAC TELESERVICES INC
<DATE-CHANGED>19950915
</FORMER-COMPANY>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>APAC CORP
<DATE-CHANGED>19950811
</FORMER-COMPANY>
</ISSUER>
<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>2009-05-08</periodOfReport>

    <issuer>
        <issuerCik>0000949297</issuerCik>
        <issuerName>APAC CUSTOMER SERVICE INC</issuerName>
        <issuerTradingSymbol>APAC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001430103</rptOwnerCik>
            <rptOwnerName>Di Bari Arthur</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O APAC CUSTOMER SERVICES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2333 WAUKEGAN ROAD, SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>BANNOCKBURN</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60015</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP, Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.53</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-05-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.53</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-05-08</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2019-05-08</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Stock option grant pursuant to the APAC Customer Services, Inc.  Amended and Restated 2005 Incentive Stock Plan.  Subject to a change in control of the Issuer, the options vest in five equal annual installments beginning on the first anniversary of the grant date, and expire 10 years from the grant date, unless earlier terminated pursuant to the terms of the Plan.  The options include the right of the Reporting Person to surrender shares to the Issuer in order to pay the exercise price of an option.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Andrew B. Szafran, Attorney-In-Fact/          Arthur D. DiBari</signatureName>
        <signatureDate>2009-05-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
