-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PAR7jxci5USMVMhIDj1DbuW+HyafwqxycF7P/7M3B89gFZFtNAIfXp8fWvuaVZ8I
 mF/sMnkIkaS5kDOplSxcJQ==

<SEC-DOCUMENT>0000016099-05-000048.txt : 20051209
<SEC-HEADER>0000016099-05-000048.hdr.sgml : 20051209
<ACCEPTANCE-DATETIME>20051209150420
ACCESSION NUMBER:		0000016099-05-000048
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051206
FILED AS OF DATE:		20051209
DATE AS OF CHANGE:		20051209

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TROPOLI PETER
		CENTRAL INDEX KEY:			0001225585

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08308
		FILM NUMBER:		051255387

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 33069
		CITY:			SAN ANTONIO
		STATE:			TX
		ZIP:			78265
		BUSINESS PHONE:		2108717509

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LUBYS INC
		CENTRAL INDEX KEY:			0000016099
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-EATING PLACES [5812]
		IRS NUMBER:				741335253
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0831

	BUSINESS ADDRESS:	
		STREET 1:		13111 NORTHWEST FREEWAY
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77040
		BUSINESS PHONE:		(713) 329 6800

	MAIL ADDRESS:	
		STREET 1:		13111 NORTHWEST FREEWAY
		STREET 2:		SUITE 600
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77040

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LUBYS CAFETERIAS INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CAFETERIAS INC
		DATE OF NAME CHANGE:	19810126
</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>2005-12-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000016099</issuerCik>
        <issuerName>LUBYS INC</issuerName>
        <issuerTradingSymbol>lub</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001225585</rptOwnerCik>
            <rptOwnerName>TROPOLI PETER</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>13111 NORTHWEST FREEWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 600</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77040</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP Administration</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-12-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.36</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2400</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The security fully vests and becomes unrestricted on 12/06/2008.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Peter Tropoli</signatureName>
        <signatureDate>2005-12-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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