-----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,
 IgN3fgD4ytOOroKu24FlwEHfynn/jzoqTqyHF9IZPiHBUrY3MrXC9iiKx8QpQBET
 O2ZNLpUSlhUzm8wtadtDkQ==

<SEC-DOCUMENT>0001104659-04-015655.txt : 20040527
<SEC-HEADER>0001104659-04-015655.hdr.sgml : 20040527
<ACCEPTANCE-DATETIME>20040527112554
ACCESSION NUMBER:		0001104659-04-015655
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040525
FILED AS OF DATE:		20040527

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STAVE JAMES W
		CENTRAL INDEX KEY:			0001240768

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22400
		FILM NUMBER:		04834033

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		302 456 6789 X 203

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STRATEGIC DIAGNOSTICS INC/DE/
		CENTRAL INDEX KEY:			0000911649
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		IRS NUMBER:				561581761
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		111 PENCADER DR
		CITY:			NEWARK
		STATE:			DE
		ZIP:			19702
		BUSINESS PHONE:		3024566789

	MAIL ADDRESS:	
		STREET 1:		111 PENCADER DR
		CITY:			NEWARK
		STATE:			DE
		ZIP:			19702

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENSYS ENVIRONMENTAL PRODUCTS INC /DE/
		DATE OF NAME CHANGE:	19930907
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-05-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000911649</issuerCik>
        <issuerName>STRATEGIC DIAGNOSTICS INC/DE/</issuerName>
        <issuerTradingSymbol>SDIX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001240768</rptOwnerCik>
            <rptOwnerName>STAVE JAMES W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>111 PENCADER DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWARK</rptOwnerCity>
            <rptOwnerState>DE</rptOwnerState>
            <rptOwnerZipCode>19702</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Vice President</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common</value>
            </securityTitle>
            <transactionDate>
                <value>2004-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12252</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>/s/ Stanley J. Musial, by power of attorney</signatureName>
        <signatureDate>2004-05-27</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----