UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549
                                        
                                        
                                    FORM 8 K
                                        
                                        
                                 CURRENT REPORT
                       Pursuant to Section 13 or 15(d) of
                      the Securities Exchange Act of 1934


Date of Report (Date of earliest event reported)         January 31, 2006
                                                -------------------------------

                               Merck & Co., Inc.
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             (Exact Name of Registrant as Specified in Its Charter)


                                   New Jersey
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                 (State or Other Jurisdiction of Incorporation)


                1-3305                                     22-1109110 
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        (Commission File Number)            (I.R.S. Employer Identification No.)


    One Merck Drive, PO Box 100, Whitehouse Station, NJ           08889-0100
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        (Address of Principal Executive Offices)                  (Zip Code)


Registrant's Telephone Number, Including Area Code            (908) 423 1000 
                                                   -----------------------------


                                 Not Applicable
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         (Former Name or Former Address, if Changed Since Last Report)


         Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

     [ ] Written communications pursuant to Rule 425 under the Securities Act
(17 CFR 230.425)

     [ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
CFR 240.14a-12)

     [ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
Exchange Act (17 CFR 240.14d-2(b))

     [ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
Exchange Act (17 CFR 240.13e-4(c))



Item 2.02. Results of Operations and Financial Condition.
--------------------------------------------------------


The following information, including the exhibits hereto, is being furnished
pursuant to this Item 2.02.

Incorporated by reference is a press release issued by the Registrant on January
31, 2006, regarding earnings for the fourth quarter 2005, attached as Exhibit
99.1.  Also incorporated by reference is certain supplemental information not
included in the press release, attached as Exhibit 99.2.

This information shall not be deemed to be "filed" for purposes of Section 18 of
the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or
otherwise subject to the liabilities of that Section, and is not incorporated by
reference in any filing under the Securities Act of 1933, as amended, or the
Exchange Act, except as expressly set forth by specific reference in such
filing. 



Item 9.01.  Financial Statements and Exhibits.
-----------------------------------------------

    (d)  Exhibits
         --------

     Exhibit 99.1    Press release issued January 31, 2006 regarding earnings
                     for fourth quarter 2005

     Exhibit 99.2    Certain supplemental information not included in the 
                     press release





                                   SIGNATURES
                                   ----------

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.




                                        Merck & Co., Inc.




Date:  January 31, 2006                 By:  /s/ Debra A. Bollwage
                                             -----------------------------   
                                                  DEBRA A. BOLLWAGE
                                                  Senior Assistant Secretary 

                                 EXHIBIT INDEX
                                 -------------



Exhibit
Number                   Description
------                   -----------


 99.1                    Press release issued January 31, 2006 regarding 
                         earnings for fourth quarter 2005

 99.2                    Certain supplemental information not included in the 
                         press release