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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 s2xPVIAPQJI9nnRF7mH9XQ==

<SEC-DOCUMENT>0001242048-06-000002.txt : 20060104
<SEC-HEADER>0001242048-06-000002.hdr.sgml : 20060104
<ACCEPTANCE-DATETIME>20060104153110
ACCESSION NUMBER:		0001242048-06-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051231
FILED AS OF DATE:		20060104
DATE AS OF CHANGE:		20060104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			JEFFERIES GROUP INC /DE/
		CENTRAL INDEX KEY:			0001084580
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				954719745
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		520 MADISON AVENUE
		STREET 2:		12TH FLOOR
		CITY:			NEW  YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		212-284-2550

	MAIL ADDRESS:	
		STREET 1:		520 MADISON AVENUE
		STREET 2:		12TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	JEF HOLDING CO INC
		DATE OF NAME CHANGE:	19990419

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DOOLEY RICHARD G
		CENTRAL INDEX KEY:			0001019553

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14947
		FILM NUMBER:		06507191

	BUSINESS ADDRESS:	
		STREET 1:		C/O MASSACHUSETTS MUTUAL LIFE INSURANCE
		STREET 2:		1295 STATE ST MAIL DROP B047
		CITY:			SPRINGFIELD
		STATE:			MA
		ZIP:			01111
		BUSINESS PHONE:		212-284-2316

	MAIL ADDRESS:	
		STREET 1:		C/O JEFFERIES & COMPANY, INC.
		STREET 2:		520 MADISON AVE., 12TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001084580</issuerCik>
        <issuerName>JEFFERIES GROUP INC /DE/</issuerName>
        <issuerTradingSymbol>JEF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001019553</rptOwnerCik>
            <rptOwnerName>DOOLEY RICHARD G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O JEFFERIES &amp; COMPANY, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>520 MADISON AVE., 12TH 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>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>585.205</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>44.98</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>185207</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Acquisition of deferred shares as a result of deferral of compensation and dividend reinvestment under the Jefferies Group, Inc. 1999 Directors' Stock Compensation Plan in a transaction exempt under Rule 16b-3(d)(1) &amp; (2) under the Securities Exchange Act of 1934.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Roland T. Kelly, by power of attorney</signatureName>
        <signatureDate>2006-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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