-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QLNB0Z65VG2faB4XrBMv/JZx8rhuKZf5vwSJJv400p9SMcYiN/PmC5Pyacr5dWYW
 mYyki2CX/KRLA1r8UGUbYg==

<SEC-DOCUMENT>0000807249-05-000104.txt : 20050419
<SEC-HEADER>0000807249-05-000104.hdr.sgml : 20050419
<ACCEPTANCE-DATETIME>20050419144041
ACCESSION NUMBER:		0000807249-05-000104
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050418
FILED AS OF DATE:		20050419
DATE AS OF CHANGE:		20050419

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			THOMAS INDUSTRIES INC
		CENTRAL INDEX KEY:			0000097886
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC LIGHTING & WIRING EQUIPMENT [3640]
		IRS NUMBER:				610505332
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4360 BROWNBORO ROAD
		STREET 2:		SUITE 300
		CITY:			LOUISVILLE
		STATE:			KY
		ZIP:			40207
		BUSINESS PHONE:		5028934600

	MAIL ADDRESS:	
		STREET 1:		4360 BROWNBORO ROAD
		STREET 2:		SUITE 300
		CITY:			LOUISVILLE
		STATE:			KY
		ZIP:			40207

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GABELLI GROUP CAPITAL PARTNERS INC
		CENTRAL INDEX KEY:			0001238894
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05426
		FILM NUMBER:		05758986

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580
		BUSINESS PHONE:		9149215100

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GABELLI MARIO J
		CENTRAL INDEX KEY:			0001185533

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05426
		FILM NUMBER:		05758987

	BUSINESS ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			16580
		BUSINESS PHONE:		9149215017

	MAIL ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GABELLI ASSET MANAGEMENT INC ET AL
		CENTRAL INDEX KEY:			0000807249
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1031

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-05426
		FILM NUMBER:		05758988

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580-1434
		BUSINESS PHONE:		9149215128

	MAIL ADDRESS:	
		STREET 1:		GABELLI FUNDS
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI FUNDS INC ET AL
		DATE OF NAME CHANGE:	19940714
</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>2005-04-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000097886</issuerCik>
        <issuerName>THOMAS INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>TII</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000807249</rptOwnerCik>
            <rptOwnerName>GABELLI ASSET MANAGEMENT INC ET AL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2>ONE CORPORATE CENTER</rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185533</rptOwnerCik>
            <rptOwnerName>GABELLI MARIO J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GABELLI ASSET MANAGEMENT INC</rptOwnerStreet1>
            <rptOwnerStreet2>ONE CORPORATE CENTER</rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001238894</rptOwnerCik>
            <rptOwnerName>GABELLI GROUP CAPITAL PARTNERS INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>140 GREENWICH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENWICH</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2700</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.5759</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11700</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.5759</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnerhsip</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The Reporting Persons have less than a 100% interest in this entity.  The amount of securities reported as beneficially owned reflects the total amount of securities held by this entity which is greater than Reporting Persons indirect pecuniary interests.  The Reporting Persons hereby disclaim beneficial ownership of these securities in excess of their pecuniary interests.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ James E. McKee                    Attorney-in-Fact for MARIO J. GABELLI and Secretary of GABELLI ASSET MANAGEMENT INC. and GGCP, INC.</signatureName>
        <signatureDate>2005-04-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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