<SUBMISSION>
<ACCESSION-NUMBER>0001022079-04-000114
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>2
<PERIOD>20040506
<FILING-DATE>20040507
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>HAGEMANN ROBERT
<CIK>0001222676
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-12215
<FILM-NUMBER>04790425
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>QUEST DIAGNOSTICS INC
<STREET2>ONE MALCOLM AVE
<CITY>TETERBORO
<STATE>NJ
<ZIP>07608
</BUSINESS-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>QUEST DIAGNOSTICS INC
<CIK>0001022079
<ASSIGNED-SIC>8071
<IRS-NUMBER>161387862
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>ONE MALCOLM AVE
<CITY>TETERBORO
<STATE>NJ
<ZIP>07608
<PHONE>2013935000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>ONE MALCOLM AVE
<CITY>TETERBORO
<STATE>NJ
<ZIP>07601
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CORNING CLINICAL LABORATORIES INC
<DATE-CHANGED>19960903
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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        <issuerTradingSymbol>DGX</issuerTradingSymbol>
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                    <footnoteId id="F1"/>
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        </nonDerivativeHolding>
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                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <value>1999-08-16</value>
            </exerciseDate>
            <expirationDate>
                <value>2009-08-16</value>
            </expirationDate>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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        <derivativeTransaction>
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                <underlyingSecurityTitle>
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                <transactionShares>
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                <underlyingSecurityTitle>
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                    <value>1953</value>
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    <footnotes>
        <footnote id="F1">These underlying shares were acquired on a periodic basis by the trustee of the Company's tax qualified Profit Sharing (401(k)) plan and/or the Company's Supplemental Deferred Compensation Plan.  The information was obtained from the plan administrator as of a recent date.  The number of shares is based on the account balance of the Company stock fund under the plan (which includes some money market instruments) divided by the market price of the Company's stock as of that date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Sirisha Gummaregula on behalf of Robert A.Hagemann</signatureName>
        <signatureDate>2004-05-07</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>hagemannpoa-050504.txt
<DESCRIPTION>POWER OF ATTORNEY
<TEXT>
POWER OF ATTORNEY


	Know all by these presents, that the undersigned
hereby constitutes and appoints each of Sirisha Gummaregula,
Michael E. Prevoznik, and Leo C. Farrenkopf, Jr., signing
singly, the undersigned's true and lawful attorney-in-fact
to:

(1)	execute for and on behalf of the undersigned, in
the undersigned's capacity as an executive officer and/or
director of Quest Diagnostics Incorporated (the "Company"),
Form ID Applications and Forms 3, 4 and 5 in accordance
with Section 16(a) of the Securities Exchange Act of
1934 and the rules thereunder;

(2)	do and perform any and all acts for and on behalf
of the undersigned which may be necessary or desirable to
complete and execute any such Form ID Application, Form 3,
4 or 5, complete and execute any amendment or amendments
thereto, and timely  file such form with the United
States Securities and Exchange Commission and any other
authority; and

(3)	take any other action of any type whatsoever in
connection with the foregoing which, in the opinion of
such attorney-in-fact, may be of benefit to, in the best
interest of, or legally required by, the undersigned, it
being understood that the documents executed by such
attorney-in-fact on behalf of the undersigned pursuant to
this Power of Attorney shall be in such form and shall
contain such terms and conditions as such attorney-in-fact
may approve in such attorney-in-fact's discretion.

	The undersigned hereby grants to each such attorney-
in-fact full power and authority to do and perform all and
every act and thing whatsoever requisite, necessary and
proper to be done in the exercise of any of the rights
and powers herein granted, as fully to all intents and
purposes as the undersigned might or could do if personally
present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-
in-fact, or such attorney-in-fact's substitute or substitutes,
shall lawfully do or cause to be done by virtue of this
power of attorney and the rights and powers herein granted.
The undersigned acknowledges that the foregoing attorneys-
in-fact, in serving in such capacity at the request of the
undersigned, are not assuming, nor is the company assuming,
any of the undersigned's responsibilities to comply with
Section 16 of the Securities Exchange Act of 1934.

	This Power of Attorney shall remain in full force
and effect until the undersigned is no longer required to
file Forms 3, 4, and 5 with respect to the undersigned's
holdings of and transactions in securities issued by the
Company, unless earlier revoked by the undersigned in a
signed writing delivered to the foregoing attorneys-in-fact.

	IN WITNESS WHEREOF, the undersigned has caused
this Power of Attorney to be executed as of this 5th day
of May, 2004.


	/s/Robert A. Hagemann
	Signature
	ROBERT A. HAGEMANN



STATE OF NEW JERSEY	)
	  ):  ss.
COUNTY OF BERGEN	)

	On this 5th day of May, 2004, before me, the
subscriber, personally appeared ROBERT A. HAGEMANN,
to me and known to me to be the same person described
in and who executed the foregoing instrument, and he
duly acknowledged to me that he executed the same.


	/s/Nanette C. Stephens
	Notary Public
	State of New Jersey ID #62221
	My commission expires 8/17/06


</TEXT>
</DOCUMENT>
</SUBMISSION>
