FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0104 Expires: January 31, 2005 Estimated average burden hours per response... 0.5

(Print or Type Responses)

1. Name and Address of Reporting Person *   YARNO WENDY L 2. Date of Event Requiring Statement (Month/Day/Year) 09/26/2006 3. Issuer Name and Ticker or Trading Symbol MERCK & CO INC [(MRK)] (Last) (First) (Middle) ONE MERCK DRIVE, P.O. BOX 100 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Marketing Officer 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) WHITEHOUSE STATION, NJ 08889-0100 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock - 401(k) Plan 14,710.6951 (1) I By 401(k) Plan

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option 1999/01/04 (right to buy)	01/04/2004	01/03/2009	Common Stock	21,100	$ 70.9722	D	Â
Employee Stock Option 1999/02/23 (right to buy)	02/23/2004	02/22/2009	Common Stock	23,737	$ 76.8372	D	Â
Employee Stock Option 2000/02/22 (right to buy)	02/22/2005	02/21/2010	Common Stock	89,674	$ 62.0859	D	Â
Employee Stock Option 2001/03/02 (right to buy)	03/02/2006	03/01/2011	Common Stock	89,674	$ 75.7638	D	Â
Employee Stock Option 2002//03/01 (right to buy)	03/01/2003(2)	02/29/2012	Common Stock	89,674	$ 58.9105	D	Â
Employee Stock Option 2003/02/28 (right to buy)	02/28/2004(3)	02/27/2013	Common Stock	89,674	$ 49.9626	D	Â
Employee Stock Option 2004/02/27 (right to buy)	02/27/2005(4)	02/26/2014	Common Stock	42,500	$ 48.24	D	Â
Employee Stock Option 2004/11/01 (right to buy)	11/01/2005(5)	10/31/2014	Common Stock	15,000	$ 28.9	D	Â
Employee Stock Option 2005/02/25 (right to buy)	02/25/2006(6)	02/24/2015	Common Stock	42,500	$ 31.84	D	Â
Employee Stock Option 2005/11/01 (right to buy)	11/01/2006(7)	10/31/2015	Common Stock	15,000	$ 28.42	D	Â
Employee Stock Option 2006/02/01 (right to buy)	02/01/2007(8)	01/31/2016	Common Stock	5,000	$ 34.47	D	Â
Employee Stock Option 2006/03/03 (right to buy)	03/03/2007(9)	03/02/2016	Common Stock	36,000	$ 35.09	D	Â
Restricted Stock Units 2004/02/27	02/27/2007	02/27/2007	Common Stock	7,083	$ (10)	D	Â
Restricted Stock Units 2005/02/25	02/25/2008	02/25/2008	Common Stock	7,083	$ (10)	D	Â
Restricted Stock Units 2006/03/03	03/03/2009	03/03/2009	Common Stock	6,750	$ (10)	D	Â
RSU - Leader Shares 2004/01/15	01/15/2007	01/15/2007	Common Stock	9,000	$ (10)	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
YARNO WENDY L ONE MERCK DRIVE P.O. BOX 100 WHITEHOUSE STATION, NJ 08889-0100	Â	Â	  Chief Marketing Officer	Â

Signatures

Wendy L. Yarno		10/06/2006
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Includes shares acquired and dividends earned through July 3, 2006 in the Merck & Co., Inc. Employee Savings and Security Plan, a 401(k) plan.
(2)	The option vests in three equal annual installments beginning March 1, 2003.
(3)	The option vests in three equal annual installments beginning February 28, 2004.
(4)	The option vests in three equal annual installments beginning February 27, 2005.
(5)	The option vests in three equal annual installments beginning November 1, 2005.
(6)	The option vests in three equal annual installments beginning February 25, 2006.
(7)	The option vests in three equal annual installments beginning November 1, 2006.
(8)	The option vests in three equal annual installments beginning February 1, 2007.
(9)	The option vests in three equal annual installments beginning March 3, 2007.
(10)	Each restricted stock unit represents a contingent right to receive one share of Merck & Co., Inc. common stock.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.