<SUBMISSION>
<ACCESSION-NUMBER>0001022079-06-000009
<TYPE>3
<PUBLIC-DOCUMENT-COUNT>2
<PERIOD>20060101
<FILING-DATE>20060106
<DATE-OF-FILING-DATE-CHANGE>20060106
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>GRANT THOMAS W II
<CIK>0001036337
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3
<ACT>34
<FILE-NUMBER>001-12215
<FILM-NUMBER>06516804
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>C/O LABONE INC
<STREET2>10310 W 84TH TERRACE PO BOX 2035
<CITY>LENEXA
<STATE>KS
<ZIP>66214
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>LABONE INC
<STREET2>10310 W 84TH TERRACE PO BOX 2035
<CITY>LENEA
<STATE>KS
<ZIP>66214
</MAIL-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>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-01-01</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001022079</issuerCik>
        <issuerName>QUEST DIAGNOSTICS INC</issuerName>
        <issuerTradingSymbol>DGX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001036337</rptOwnerCik>
            <rptOwnerName>GRANT THOMAS W II</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>QUEST DIAGNOSTICS</rptOwnerStreet1>
            <rptOwnerStreet2>1290 WALL STREET WEST</rptOwnerStreet2>
            <rptOwnerCity>LYNDHURST</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07071</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr.VP, Insurance/Employee Serv</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5267</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>Sirisha Gummaregula, atty-in-fact for W. Thomas Grant II</signatureName>
        <signatureDate>2006-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>tgrantpoa.txt
<DESCRIPTION>POWER OF ATTORNEY
<TEXT>
POWER OF ATTORNEY

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

(1) execute for and on behalf of the
undersigned Forms 3, 4 and 5 in
accordance with Section 16(a) rules
hereunder;

(2) do and perform any and all acts for
and on behalf of the undersigned which
may be necessary or desirable to complete
the execution of any such Form 3,4 or 5
and the timely filing of 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
document executed 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 his
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 ofthe rights
and powers herein granted, as full 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 attorney-in-fact,in serving in
such capacity at the request of the
undersigned, are not assuming any of the
undersigned's responsibilitiesto comply with
Section 16 of the Securities Exchange Act
of 1934.

IN WITNESS WHEREOF, the undersigned has
caused this Power of Attorney to be
executed as of this 19th day of
December, 2005.
/s/ W. Thomas Grant II
Signature
W. Thomas Grant II

STATE OF KANSAS    )
	  	   ):ss.
COUNTY OF Johnson  )

On this 19th day of December, 2005, before
me,the subscriber, personally appeared
W. Thomas Grant II, 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/ Barb Cox
Notary Public, State of Kansas
My Commission Expires 2-7-09

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