-----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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 kK/+wHRMZgtAlStwEfs4RQ==

<SEC-DOCUMENT>0000799729-06-000021.txt : 20061030
<SEC-HEADER>0000799729-06-000021.hdr.sgml : 20061030
<ACCEPTANCE-DATETIME>20061030154221
ACCESSION NUMBER:		0000799729-06-000021
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061030
FILED AS OF DATE:		20061030
DATE AS OF CHANGE:		20061030

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PAREXEL INTERNATIONAL CORP
		CENTRAL INDEX KEY:			0000799729
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMMERCIAL PHYSICAL & BIOLOGICAL RESEARCH [8731]
		IRS NUMBER:				042776269
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		195 WEST ST
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		7814879900

	MAIL ADDRESS:	
		STREET 1:		195 WEST ST
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WINSCHEL JAMES F JR
		CENTRAL INDEX KEY:			0001224653

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21244
		FILM NUMBER:		061171977

	BUSINESS ADDRESS:	
		STREET 1:		C/O PAREXEL INTERNATIONAL CORP
		STREET 2:		195 WEST ST
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		7814344158

	MAIL ADDRESS:	
		STREET 1:		195 WEST STREET
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-10-30</periodOfReport>

    <issuer>
        <issuerCik>0000799729</issuerCik>
        <issuerName>PAREXEL INTERNATIONAL CORP</issuerName>
        <issuerTradingSymbol>PRXL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001224653</rptOwnerCik>
            <rptOwnerName>WINSCHEL JAMES F JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PAREXEL INTERNATIONAL CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>200 WEST STREET</rptOwnerStreet2>
            <rptOwnerCity>WALTHAM</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02451</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP &amp; CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-10-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.54</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>67984</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-10-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.54</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5852</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Owned by sons.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>200</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Owned by wife.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 346 shares of common stock acquired pursuant to the Issuer's 2000 Employee Stock Purchase Plan.</footnote>
        <footnote id="F2">The reporting person disclaims beneficial ownership of all securities held by his wife and sons, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the shares for purposes of Section 16 or for any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>James F. Winschel, Jr.</signatureName>
        <signatureDate>2006-10-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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