-----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,
 FuioDx42fbJ98hW0Tfo63m80pYOFWuhR0sml8hMv1pZVpVELlB2jXKtzsuctlVgN
 BVlB5SkCK3g7ep53zHSYUQ==

<SEC-DOCUMENT>0000029002-06-000021.txt : 20060524
<SEC-HEADER>0000029002-06-000021.hdr.sgml : 20060524
<ACCEPTANCE-DATETIME>20060524131308
ACCESSION NUMBER:		0000029002-06-000021
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060522
FILED AS OF DATE:		20060524
DATE AS OF CHANGE:		20060524

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DIODES INC /DEL/
		CENTRAL INDEX KEY:			0000029002
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				952039518
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3050 E HILLCREST DR
		CITY:			WESTLAKE VILLAGE
		STATE:			CA
		ZIP:			91362
		BUSINESS PHONE:		8054464800

	MAIL ADDRESS:	
		STREET 1:		3050 E HILLCREST DR SUITE 200
		STREET 2:		3050 E HILLCREST DR SUITE 200
		CITY:			WESTLAKE VILLAGE
		STATE:			CA
		ZIP:			913623154

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LU M K
		CENTRAL INDEX KEY:			0001196529

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	002-25577
		FILM NUMBER:		06863593

	MAIL ADDRESS:	
		STREET 1:		C/O DIODES INC
		STREET 2:		3050 E HILLCREST DR
		CITY:			WESTLAKE
		STATE:			CA
		ZIP:			91362
</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>2006-05-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000029002</issuerCik>
        <issuerName>DIODES INC /DEL/</issuerName>
        <issuerTradingSymbol>DIOD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001196529</rptOwnerCik>
            <rptOwnerName>LU M K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O DIODES INC</rptOwnerStreet1>
            <rptOwnerStreet2>3050 E HILLCREST DR</rptOwnerStreet2>
            <rptOwnerCity>WESTLAKE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>91362</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Award (RSA)</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2006-05-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Awards vest in 4 equal annual installments beginning 05/22/2007.</footnote>
        <footnote id="F2">Awards granted under Rule 16b-3 Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Carl C. Wertz as Power of Attorney for M.K. Lu</signatureName>
        <signatureDate>2006-05-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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