PROSPECTUS SUPPLEMENT
(To Prospectus dated June 18, 1997)

              4,000,000 Trust Convertible Preferred Securities
                          McKesson Financing Trust
                 5% Trust Convertible Preferred Securities
        (Liquidation Amount $50 per Convertible Preferred Security)
               Guaranteed to the Extent Set Forth Herein by,
                            McKesson Corporation


      This prospectus supplement supplements and amends the prospectus
dated June 18, 1997, relating to the 5% Trust Convertible Preferred
Securities of McKesson Corporation ("McKesson"). The Convertible Preferred
Securities represent preferred undivided beneficial interests in the assets
of McKesson Financing Trust, a statutory business trust formed under the
laws of the State of Delaware, and the shares of McKesson common stock, par
value $.01 per share, issuable upon conversion of the Convertible Preferred
Securities.

      On October 17, 1998, McKesson and HBO & Company ("HBOC"), a leading
healthcare information company, signed a definitive merger agreement for
McKesson to acquire HBOC. Under the terms of the merger agreement,
stockholders of HBOC would receive 0.37 shares of McKesson common stock for
each share of HBOC common stock in a tax-free exchange. The merger of the
two companies, which is subject to the approval of the stockholders of
McKesson and HBOC at meetings scheduled to occur on January 12, 1999, and
other customary conditions, would be accounted for as a pooling of
interests and is anticipated to close in the first quarter of 1999. The new
company would be named McKesson HBOC, and the corporate headquarters of
McKesson HBOC would be located in San Francisco, California.

      Upon completion of the merger, Charles W. McCall, currently president
and chief executive officer of HBOC, would become chairman of McKesson
HBOC's board of directors, and Mark A. Pulido, currently president and
chief executive officer of McKesson, would become president and chief
executive officer of McKesson HBOC. Also upon completion of the merger,
McKesson HBOC's board of directors would consist of ten members, which
would include five members from the current McKesson board and five members
from the current HBOC board.

      The table on pages 56 through 58 of the prospectus, which sets forth
information with respect to the Selling Holders (as defined in the
prospectus) and the respective amounts of Convertible Preferred Securities
beneficially owned by each Selling Holder that may be offered pursuant to
the prospectus (as supplemented and amended), is hereby amended by the
deletion of items 90 and 92 of that table and the substitution therefor of
items 90 and 92 below as follows:




                          Convertible Preferred     Number of          Convertible Preferred
                          Securities Owned         Convertible           Securities Owned
                          Prior to Offering         Preferred             After Offering
                                                 Securities Offered    
"Selling Holder            Number      Percent                            Number        Percent
- ---------------            ------      -------                            ------        -------
                                                                            
90. Prudential  
     Securities Inc.        5,000        0.125%       5,000                  0           0.00%

92. Merrill Lynch Pierce 
     Fenner & Smith Inc.   20,000        0.500%      20,000                  0           0.00%




    The Prospectus, together with this Prospectus Supplement, constitutes
the prospectus required to be delivered by Section 5(b) of the Securities
Act of 1933, as amended, with respect to offers and sales of the
Convertible Preferred Securities and McKesson Common Stock issuable upon
conversion of the Convertible Preferred Securities. All references in the
Prospectus to "this Prospectus" are hereby amended to read "this Prospectus
(as supplemented and amended)".

Consider carefully the risk factors above and beginning on page 6 in this
prospectus.

Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved of these securities or passed upon
the adequacy or accuracy of this prospectus. Any representation to the
contrary is a criminal offense.

This prospectus supplement is dated December 7, 1998.