As filed with the Securities and Exchange Commission on June 20, 2001
                                                      Registration No. 333-57012
================================================================================

                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549
                               ________________

                                POST-EFFECTIVE
                                AMENDMENT NO. 1
                                      to
                                   FORM S-8
                            REGISTRATION STATEMENT
                                     under
                          THE SECURITIES ACT OF 1933
                               ________________

                         VARIAN MEDICAL SYSTEMS, INC.
            (Exact name of Registrant as specified in its charter)

                   Delaware                               94-2359345
           (State of incorporation)         (I.R.S. Employer Identification No.)

                                3100 Hansen Way
                       Palo Alto, California 94304-1129
                   (Address of principal executive offices)
                            _______________________

                 Varian Medical Systems, Inc. Retirement Plan
                           (Full title of the Plan)
                            _______________________

                                Joseph B. Phair
         Vice President, Administration, General Counsel and Secretary
                         Varian Medical Systems, Inc.
                                3100 Hansen Way
                           Palo Alto, CA 94304-1129
                                (650) 493-4000
(Name, address and telephone number, including area code, of agent for service)


================================================================================


                                    PART I

Item 1.   Plan Information.*
          ----------------

Item 2.   Registrant Information and Employee Plan Annual Information.*
          -----------------------------------------------------------

*  Information required by Part I to be contained in the Section 10(a)
prospectus is omitted from this Registration Statement in accordance with Rule
428 under the Securities Act of 1933 (the "Securities Act") and the Note to Part
I of Form S-8.

                                    PART II


Item 3.   Incorporation of Documents by Reference.
          ---------------------------------------

     Varian Medical Systems, Inc. (the "Registrant") hereby incorporates by
reference into this Registration Statement the following documents filed with
the Securities and Exchange Commission (the "Commission"):

     (a)  The Registrant's Annual Report on Form 10-K for the fiscal year ended
September 29, 2000.

     (b)  The Registrant's Quarterly Reports on Form 10-Q for the quarters ended
December 29, 2000 and March 30, 2001.

     (c)  The description of Registrant's Common Stock and preferred stock
purchase rights contained in the Registrant's Registration Statements on Form 8-
A, including any subsequent amendments or reports filed for the purpose of
updating such information.

     (d)  The Annual Report on Form 11-K of the Varian Medical Systems, Inc.
Retirement Plan for the fiscal year ended September 29, 2000.

     All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 (the "Exchange
Act") shall be deemed incorporated by reference in this Registration Statement
and to be a part hereof from the date of filing such documents until a post-
effective amendment of this Registration Statement is filed which indicates that
all securities being offered hereby have been sold or which deregisters all
securities then remaining unsold.

Item 4.   Description of Securities.  Not applicable.
          -------------------------

Item 5.   Interests of Named Experts and Counsel.
          --------------------------------------

     The legality of the securities offered hereby has been passed on for the
Registrant by Joseph B. Phair.  Mr. Phair is Vice President, Administration
General Counsel and Secretary of the Registrant, and as of May 31, 2001,
beneficially owned 87,573 shares of the Registrant's Common Stock, which
includes 62,630 shares which may be acquired within 60 days upon the exercise of
options and 2,825 shares owned by his children living in his household.

Item 6.   Indemnification of Directors and Officers.
          -----------------------------------------

     Section 102 of the Delaware General Corporation Law allows a corporation to
eliminate the personal liability of a director to the corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director,
subject to certain exceptions. Article TENTH of the Registrant's Restated
Certificate of Incorporation eliminates the personal liability of the
Registrant's directors to the Registrant or its stockholders for monetary
damages for breach of a director's fiduciary duty, except for liability:  (1)
under Section 174 of the Delaware General Corporation Law; (2) for breach of a
director's duty of loyalty to the Registrant or its stockholders; (3) for

                                       1


acts or omissions not in good faith or involving intentional misconduct or
knowing violations of law; or (4) for any transaction from which the director
derived an improper personal benefit.

     Section 145 of the Delaware General Corporation Law grants to each
corporation organized thereunder the power to indemnify its officers and
directors for certain acts.  Article NINTH of the Registrant's By-laws sets
forth the extent to which officers and directors of the Registrant may be
indemnified against any liabilities which they may incur in their capacities as
directors or officers of the Registrant.  Article NINTH provides, in part, that
each person who was or is made a party or is threatened to be made a party or is
involved in any action, suit or proceeding by reason of the fact that he or she
is or was a director or officer of the Registrant or is or was serving at the
request of the Registrant as a director, officer, employee or agent of another
corporation, limited liability company, partnership, joint venture, trust or
other enterprise, including service with respect to an employee benefit plan,
shall be indemnified and held harmless by the Registrant, to the fullest extent
authorized by the Delaware General Corporation Law and any other applicable
laws, against all expense, liability and loss (including attorneys' fees,
judgments, fines, ERISA excise taxes or penalties and amounts paid or to be paid
in settlement) reasonably incurred or suffered by such person in connection with
such proceeding; provided, however, that if the person seeking indemnification
initiated the proceeding in respect to which he or she is seeking
indemnification from the Registrant, the Registrant shall provide such
indemnification only if such proceeding was authorized by the Registrant's Board
of Directors.

     The Registrant has, and intends in the future to enter into, agreements to
provide indemnification for directors and officers in addition to that contained
in the Restated Certificate of Incorporation and By-laws. The indemnification
agreements require the Registrant, among other things, to indemnify officers and
directors against liabilities that may arise by reason of their status or
service as officers, directors, employees, trustees, partners, agents or
fiduciaries of the Registrant (but not for liabilities arising from conduct
entered into in bad faith or conduct which the officer or director did not
reasonably believe to be in the best interest of the Registrant), and to advance
sums covering the expenses they incurred as a result of any proceeding against
them with respect to which they are indemnified under such indemnification
agreement.

Item 7.  Exemption from Registration Claimed.  Not applicable.
         -----------------------------------

Item 8.  Exhibits.
         --------

     (a)     Exhibit
             Number
             ------

             5.1        Opinion of Joseph B. Phair, Esq., Vice President,
                        Administration, General Counsel and Secretary to
                        Registrant.*

             23.1       Consent of Joseph B. Phair, Esq., Vice President,
                        Administration, General Counsel and Secretary to
                        Registrant (included in Exhibit 5.1).*

             23.2       Consent of Independent Accountants.

             24.1       Powers of Attorney.*

             99.1       Varian Medical Systems, Inc. Retirement Plan.*

     (b) The Registrant will submit the Varian Medical Systems, Inc. Retirement
Plan (the "Plan") and any amendments thereto to the Internal Revenue Service
("IRS") in a timely manner and will make all changes required by the IRS in
order to qualify the Plan.


_____________________

*    Previously filed

                                       2


Item 9.     Undertakings.
            ------------

       (a)  The Registrant hereby undertakes:

            (1)  to file, during any period in which offers or sales are being
made, a post-effective amendment to this Registration Statement:

                 (i)   to include therein any prospectus required by section
     10(a)(3) of the Securities Act;

                 (ii)  to reflect in such prospectus any facts or events arising
     after the effective date of this Registration Statement (or the most recent
     post-effective amendment thereof) which, individually or in the aggregate,
     represent a fundamental change in the information set  forth herein; and

                 (iii) to include any material information with respect to the
     plan of distribution not previously disclosed in this Registration
     Statement or any material change to such information in this Registration
     Statement;

provided, however, that clauses (a)(1)(i) and (a)(1)(ii) do not apply if the
information required to be included in a post-effective amendment by those
clauses is contained in periodic reports filed by the Registrant pursuant to
section 13 or section 15(d) of the Exchange Act that are incorporated by
reference into this Registration Statement;

            (2)  that, for purposes of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof; and

            (3)  to remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the Varian Medical Systems, Inc. Salaried Employees' Savings
Plan.

     (b)    The Registrant hereby undertakes that, for purposes of determining
any liability under the Securities Act, each filing of the Registrant's annual
report pursuant to section 13(a) or section 15(d) of the Exchange Act (and,
where applicable, each filing of an employee benefit plan's annual report
pursuant to section 15(d) of the Exchange Act) that is incorporated by reference
into this Registration Statement shall be deemed to be a new registration
statement relating to the securities offered therein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof.

     (c)    Insofar as the indemnification for liabilities arising under the
Securities Act may be permitted for directors, officers and controlling persons
of the Registrant pursuant to the foregoing provisions, or otherwise, the
Registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in a successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered hereunder, the Registrant will, unless in the opinion of its counsel
the question has already been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question of whether such indemnification
by it is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue.

                                       3


                                  SIGNATURES

THE REGISTRANT

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Registrant, a corporation organized and existing under the laws of the State of
Delaware, certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Palo Alto, State of California, on this 20th day of
June, 2001.

                                 VARIAN MEDICAL SYSTEMS, INC.


                                 By:  /s/ Joseph B. Phair
                                      ----------------------------------------
                                      Joseph B. Phair
                                      Vice President, Administration, General
                                      Counsel and Secretary

Pursuant to the requirements of the Securities Act of 1933, as amended, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.



           Signature                             Title                           Date
           ---------                             -----                           ----
                                                                    
                                                                            June 20, 2001
*Richard M. Levy                        Director, President and
                                        Chief Executive Officer
                                     (Principal Executive Officer)
                                                                            June 20, 2001
  /s/ Elisha W. Finney                Vice President, Finance and
- -------------------------------         Chief Financial Officer
  Elisha W. Finney                 (Principal Financial Officer and
                                     Principal Accounting Officer)
                                                                            June 20, 2001
*David W. Martin, Jr.                          Director
                                                                            June 20, 2001
*Richard W. Vieser                             Director
                                                                            June 20, 2001
*John Seely Brown                              Director
                                                                            June 20, 2001
*Samuel Hellman                                Director
                                                                            June 20, 2001
*Terry R. Lautenbach                           Director
                                                                            June 20, 2001
*Burton Richter                                Director

*By:    /s/ Joseph B. Phair
    --------------------------
    Joseph B. Phair
    Attorney-in-fact


                                       4


THE PLAN

     Pursuant to the requirements of the Securities Act of 1933, the trustee (or
other persons who administer the employee benefit plan) have duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized in the City of Palo Alto, State of California on this 20th day
of June 2001.

                                 THE VARIAN MEDICAL SYSTEMS, INC. RETIREMENT
                                 PLAN



                                 By:  Varian Medical Systems, Inc.



                                 By:  /s/ Joseph B. Phair
                                      ---------------------------------------
                                      Joseph B. Phair
                                      Vice President, Administration, General
                                      Counsel and Secretary

                                       5


                                 EXHIBIT INDEX

Exhibit
Number
- ------

 5.1      Opinion of Joseph B. Phair, Esq., Vice President, Administration,
          General Counsel and Secretary to Registrant.*

 23.1     Consent of Joseph B. Phair, Esq., Vice President, Administration,
          General Counsel and Secretary to Registrant (included in Exhibit
          5.1).*

 23.2     Consent of Independent Accountants.

 24.1     Powers of Attorney.*

 99.1     Varian Medical Systems, Inc. Retirement Plan.*


___________________________

*  Previously filed