FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN 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

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(Print or Type Responses)

1. Name and Address of Reporting Person * JULIAN PAUL C   2. Issuer Name and Ticker or Trading Symbol MCKESSON CORP [MCK] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) EVP, Group President (Last) (First) (Middle) ONE POST STREET 3. Date of Earliest Transaction (Month/Day/Year) 05/22/2009 (Street) SAN FRANCISCO, CA 94104 4. If Amendment, Date Original Filed(Month/Day/Year) 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 Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 05/22/2009   M   38,610 A $ 0 38,667 D   Common Stock 05/22/2009   F   15,219 (1) D $ 40.89 23,448 D   Common Stock 05/23/2009   M   72,000 A $ 0 95,448 D   Common Stock 05/23/2009   F   32,940 (1) D $ 40.89 62,508 D   Common Stock 05/25/2009   M   70,000 A $ 0 132,508 D   Common Stock 05/25/2009   F   32,025 (1) D $ 40.89 100,483 D   Common Stock 05/26/2009   S   100,426 (2) D $ 39.9338 57 D   Common Stock               325.7639 I By Profit-Sharing Investment Plan

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

1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Underlying Securities (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	$ 0	05/22/2009		M			38,610	(3)	(3)	Common Stock	38,610	$ 0	38,610	D
Restricted Stock Units	$ 0	05/23/2009		M			72,000	(4)	(4)	Common Stock	72,000	$ 0	0	D
Restricted Stock Units	$ 0	05/25/2009		M			70,000	(5)	(5)	Common Stock	70,000	$ 0	0	D
Restricted Stock Units	$ 0	05/26/2009		A		133,575		(6)	(6)	Common Stock	133,575	$ 0	133,575	D
Employee Stock Option (Right-to-buy)	$ 40.46	05/26/2009		A		339,000		(7)	05/26/2016	Common Stock	339,000	$ 0	339,000	D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
JULIAN PAUL C ONE POST STREET SAN FRANCISCO, CA 94104			EVP, Group President

Signatures

Donna Spinola, Attorney-in-fact		05/27/2009
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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)	This transaction represents a withholding of shares to cover taxes applicable to a vesting of RSUs, also reported on this Form 4.
(2)	Sale made pursuant to a previously adopted plan dated 3/11/2009, intended to comply wiht Rule 10b5-1(c).
(3)	These units vest 50% on 5/22/2009 and 50% on 5/22/2011.
(4)	These units vest 50% on 5/23/2007 and 50% on 5/23/2009.
(5)	These units vest 100% on 5/25/2009.
(6)	These units vest 100% on 5/20/2012.
(7)	This option granted 5/26/2009 vests 25% per year commencing on the first anniversary of the grant date.

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