<SUBMISSION>
<ACCESSION-NUMBER>0001206774-04-000285
<TYPE>3
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20040312
<FILING-DATE>20040406
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>AMERICAN PACIFIC CORP
<CIK>0000350832
<ASSIGNED-SIC>2810
<IRS-NUMBER>596490478
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>0930
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>3770 HOWARD HUGHES PKWY STE 300
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89109
<PHONE>7027352200
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>3770 HOWARD HUGHES PKWY STE 300
<STREET2>3770 HOWARD HUGHES PKWY STE 300
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89109
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>VAN VOORHEES SETH
<CIK>0001284934
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3
<ACT>34
<FILE-NUMBER>001-08137
<FILM-NUMBER>04719177
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>3770 HOWARD HUGHES PKWY
<STREET2>SUITE 300
<CITY>LAS VEGAS
<STATE>NV
<ZIP>89109
<PHONE>7027352200
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>12 HARVEY DRIVE
<CITY>SHORT HILLS
<STATE>NJ
<ZIP>07078
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>apc71161_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2004-03-12</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000350832</issuerCik>
        <issuerName>AMERICAN PACIFIC CORP</issuerName>
        <issuerTradingSymbol>APFC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001284934</rptOwnerCik>
            <rptOwnerName>VAN VOORHEES SETH</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3770 HOWARD HUGHES PKWY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 300</rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89109</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">No securities are beneficially owned by Reporting Person.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Seth Van Voorhees</signatureName>
        <signatureDate>2004-04-05</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
