<SEC-DOCUMENT>0001257640-12-000011.txt : 20120514
<SEC-HEADER>0001257640-12-000011.hdr.sgml : 20120514
<ACCEPTANCE-DATETIME>20120514172408
ACCESSION NUMBER:		0001257640-12-000011
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120511
FILED AS OF DATE:		20120514
DATE AS OF CHANGE:		20120514

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KRONOS WORLDWIDE INC
		CENTRAL INDEX KEY:			0001257640
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INORGANIC CHEMICALS [2810]
		IRS NUMBER:				760294959
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5430 LBJ FREEWAY
		STREET 2:		SUITE 1700
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75240
		BUSINESS PHONE:		9722331700

	MAIL ADDRESS:	
		STREET 1:		5430 LBJ FREEWAY
		STREET 2:		SUITE 1700
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75240

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KRONOS INC
		DATE OF NAME CHANGE:	20030730

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			POSTON GEORGE E
		CENTRAL INDEX KEY:			0001188419

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31763
		FILM NUMBER:		12839880

	MAIL ADDRESS:	
		STREET 1:		C/O ANDY LOUIS
		STREET 2:		5430 LBJ FREEWAY, SUITE 1700
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75240
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0305</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-05-11</periodOfReport>

    <issuer>
        <issuerCik>0001257640</issuerCik>
        <issuerName>KRONOS WORLDWIDE INC</issuerName>
        <issuerTradingSymbol>KRO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001188419</rptOwnerCik>
            <rptOwnerName>POSTON GEORGE E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5430 LBJ FREEWAY, SUITE 1700</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75240</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 $0.01 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2012-05-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.49</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>A. Andrew R. Louis, Attorney-in-fact, for George E. Poston</signatureName>
        <signatureDate>2012-05-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
