As filed with the Securities and Exchange Commission on November 12, 2002

                                              Securities Act File No. 333-97055
                                       Investment Company Act File No. 811-4077
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                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549
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                                   FORM N-14
                            REGISTRATION STATEMENT
                                     UNDER
                          THE SECURITIES ACT OF 1933
                        ------------------------------

      [ ] Pre-Effective Amendment No. [X] Post-Effective Amendment No. 1

                       (Check appropriate box or boxes)
                        ------------------------------

                  MERRILL LYNCH U.S. GOVERNMENT MORTGAGE FUND
            (Exact Name of Registrant as Specified in its Charter)
                        ------------------------------

                                (609) 282-2800
                       (Area Code And Telephone Number)
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                            800 Scudders Mill Road
                         Plainsboro, New Jersey 08536
                   (Address of Principal Executive Offices:
                    Number, Street, City, State, Zip Code)
                        ------------------------------

                                Terry K. Glenn
                  Merrill Lynch U.S. Government Mortgage Fund
             800 Scudders Mill Road, Plainsboro, New Jersey 08536
       Mailing Address: P.O. Box 9011, Princeton, New Jersey 08543-9011
                    (Name and Address of Agent for Service)
                        ------------------------------

                                  Copies to:

 Philip L. Kirstein, Esq.                        Frank P. Bruno, Esq.
Fund Asset Management, L.P.                 Sidley Austin Brown and Wood, LLP
      P.O. Box 9011                               787 Seventh Avenue
Plainsboro, NJ 08543-9011                         New York, NY 10019

                        ------------------------------

     Title of Securities Being Registered: Shares of beneficial interest, par
value $.10 per share.

     No filing fee is required because of reliance on Section 24(f) of the
Investment Company Act of 1940, as amended.
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     This Post-Effective Amendment No. 1 to the Registrant's Registration
Statement on Form N-14 (File No. 333-97055) (the "N-14 Registration
Statement") of Merrill Lynch U.S. Government Mortgage Fund (the "Registrant")
consists of the following:

(1)  Facing Sheet of this Registration Statement.

(2)  Part C of this Registration Statement (including signature page).

Parts A and B are incorporated herein by reference from the Combined Proxy
Statement and Prospectus filed on September 3, 2002 pursuant to Rule 497 under
the Securities Act of 1933, as amended (the "Securities Act").

     This Post-Effective Amendment No. 1 to the N-14 Registration Statement is
being filed solely to file an opinion of Sidley Austin Brown & Wood LLP, tax
counsel for the Registrant, as Exhibit 12 to the N-14 Registration Statement.
The tax opinion relates to the reorganization of Mercury U.S. Government
Securities Fund, a series of The Asset Program, Inc., into the Registrant.



                                      2



                                    PART C

                               OTHER INFORMATION

Item 15.  Indemnification.

     Section 5.3 of the Declaration of Trust of Merrill Lynch U.S. Government
Mortgage Fund (the "Registrant") provides as follows:

     "The Trust shall indemnify each of its Trustees, officers, employees, and
agents (including persons who serve at its request as directors, officers or
trustees of another organization in which it has any interest as a
shareholder, creditor or otherwise) against all liabilities and expenses
(including amounts paid in satisfaction of judgments, in compromise, as fines
and penalties, and as counsel fees) reasonably incurred by him in connection
with the defense or disposition of any action, suit or other proceeding,
whether civil or criminal, in which he may be involved or with which he may be
threatened, while in office or thereafter, by reason of his being or having
been such a trustee, officer, employee or agent, except with respect to any
matter as to which he shall have been adjudicated to have acted in bad faith,
willfull misfeasance, gross negligence or reckless disregard of his duties;
provided, however, that as to any matter disposed of by a compromise payment
by such person, pursuant to a consent decree or otherwise, no indemnification
either for said payment or for any other expenses shall be provided unless the
Trust shall have received a written opinion from independent legal counsel
approved by the Trustees to the effect that if either the matter of willful
misfeasance, gross negligence or reckless disregard of duty, or the matter of
good faith and reasonable belief as to the best interests of the Trust, had
been adjudicated, it would have been adjudicated in favor of such person. The
rights accruing to any Person under these provisions shall not exclude any
other right to which he may be lawfully entitled; provided that no Person may
satisfy any right of indemnity or reimbursement granted herein or in Section
5.1 or to which he may be otherwise entitled except out of the property of the
Trust, and no shareholder shall be personally liable to any Person with
respect to any claim for indemnity or reimbursement or otherwise. The Trustees
may make advance payments in connection with indemnification under this
Section 5.3, provided that the indemnified person shall have given a written
undertaking to reimburse the Trust in the event it is subsequently determined
that he is not entitled to such indemnification."

     Insofar as the conditional advancing of indemnification moneys for
actions based upon the Investment Company Act of 1940 may be concerned, such
payments will be made only on the following conditions: (i) the advances must
be limited to amounts used, or to be used, for the preparation or presentation
of a defense to the action, including costs connected with the preparation of
a settlement; (ii) advances may be made only upon receipt of a written promise
by, or on behalf of, the recipient to repay that amount of the advance which
exceeds the amount to which it is ultimately determined that he is entitled to
receive from the Registrant by reason of indemnification; and (iii) (a) such
promise must be secured by a surety bond, other suitable insurance or an
equivalent form of security which assures that any repayments may be obtained
by the Registrant without delay or litigation, which bond, insurance or other
form of security must be provided by the recipient of the advance, or (b) a
majority of a quorum of the Registrant's disinterested, non-party Trustees, or
an independent legal counsel in a written opinion, shall determine, based upon
a review of readily available facts, that the recipient of the advance
ultimately will be found entitled to indemnification.

     In Section 9 of the Distribution Agreement relating to the securities
being offered hereby, the Registrant agrees to indemnify the Distributor of
each person, if any, who controls the Distributor within the meaning of the
Securities Act of 1933, as amended (the "Act") against certain types of civil
liabilities arising in connection with the Registration Statement or
Prospectus and Statement of Additional Information.

     Insofar as indemnification for liabilities arising under the Act may be
permitted to Trustees, officers and controlling persons of the Registrant and
the principal underwriter pursuant to the foregoing provisions or otherwise,
the Registrant has been advised that in the opinion of the Securities and
Exchange Commission such indemnification is against public policy as expressed
in the 1933 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 Trustee, officer or controlling
person of the Registrant and the principal underwriter in connection with the
successful defense of any action, suit or proceeding) is asserted by such
Trustee, officer or controlling person or the principal underwriter in
connection with the shares being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the



question whether such indemnification by it is against public policy as
expressed in the Act and will be governed by the final adjudication of such
issue.



Item 16.  Exhibits.

(1)(a)   -- Declaration of Trust of the Registrant, dated July 20, 1984.(a)
(1)(b)   -- Certification of Amendment, dated December 20, 1991, to Declaration
            of Trust.(b)
(1)(c)   -- Instrument establishing Class A and Class B shares of the
            Registrant.(b)
(1)(d)   -- Certification of Amendment, dated October 13, 1994, to Declaration
            of Trust and Instrument establishing Class C and Class D shares of
            the Registrant.(c)
(1)(e)   -- Certification of Amendment, dated April 18, 2000, to Declaration of
            Trust.(d)
(2)      -- Amended By-Laws of the Registrant.(e)
(3)         Not applicable.
(4)         Form of Agreement and Plan of Reorganization between the Registrant
            and The Asset Program Inc. (the "Asset Program") on behalf of
            Mercury U.S. Government Securities Fund ("Mercury Fund")(f)
(5)         Portions of the Declaration of Trust, as amended and supplemented,
            and the By-Laws of the Registrant defining rights of stockholders
            of the Registrant.(g)
(6)(a)   -- Management Agreement between the Registrant and Fund Asset
            Management, L.P.(h)
(6)(b)      Supplement to Management Agreement between the Registrant and Fund
            Asset Management, L.P.(i)
(7)(a)   -- Form of Distribution Agreement between the Registrant and FAM
            Distributors, Inc. (the "Distributor").(j)
(8)      -- None.
(9)      -- Custody Agreement between the Registrant and The Bank of New
            York.(k)
(10)(a)     Form of Amended and Restated Class B Shares Distribution Plan of
            the Registrant.(l)
(10)(b)  -- Form of Amended and Restated Class C Shares Distribution Plan of
            the Registrant.(l)
(10)(c)  -- Form of Amended and Restated Class D Shares Distribution Plan of
            the Registrant.(l)
(10)(d)  -- Merrill Lynch Select PricingSM System Plan pursuant to Rule
            l8f-3.(m)
(11)     -- Opinion and Consent of Sidley Austin Brown & Wood LLP, counsel for
            the Registrant.(n)
(12)     -- Opinion of Sidley Austin Brown & Wood LLP, counsel for the
            Registrant and Asset Program.
(13)     -- Not applicable.
(14)(a)  -- Consent of Deloitte & Touche LLP, independent auditors for the
            Registrant.(n)
(14)(b)  -- Consent of Deloitte & Touche LLP, independent auditors for Asset
            Program.(n)
15)      -- Not applicable.
(16)     -- Power of Attorney.(o)
(17)(a)  -- Prospectus dated December 19, 2001, and Statement of Additional
            Information dated December 19, 2001, of the Registrant.(n)
(17)(b)     Annual Report to Stockholders of the Registrant.(n)
(17)(c)     Semi-Annual Report to Stockholders of the Registrant.(n)
(17)(d)     Prospectus dated May 29, 2002, and Statement of Additional
            Information dated May 29, 2002, of Mercury Fund, a series of Asset
            Program.(n)
(17)(e)     Annual Report to Stockholders of Mercury Fund, a series of Asset
            Program.(n)



   ---------------
   (a) Incorporated by reference to Exhibit 1(a) to the Pre-Effective
       Amendment to the Registrant's Registration Statement on Form N-1A under
       the Securities Act of 1933, as amended ("Registration Statement"),
       filed on July 24, 1984, and refiled with Post-Effective Amendment No.
       12 on December 21, 1995 pursuant to the Electronic Data Gathering,
       Analysis and Retrieval ("EDGAR") requirements.
   (b) Incorporated by reference to Exhibit 1(b) to Post-Effective Amendment
       No. 8 to the Registration Statement filed on August 8, 1984, and
       refiled with Post-Effective Amendment No. 12 on December 21, 1995
       pursuant to EDGAR requirements.
   (c) Incorporated by reference to Exhibit 1(d) to Post-Effective Amendment
       No. 11 to the Registration Statement, filed on October 12, 1994.
   (d) Incorporated by reference to Exhibit 1(e) to Post-Effective Amendment
       No. 18 to the Registration Statement, filed on November 29, 2000.
   (e) Incorporated by reference to Exhibit 2(b) to Post-Effective Amendment
       No. 19 to the Registration Statement, filed on December 19, 2001.
   (f) Included as Exhibit I to the Proxy Statement and Prospectus contained
       in the Registrant's registration statement on Form N-14.
   (g) Reference is made to Article II, Section 2.3 and Article III, V, VI,
       VIII, IX, X and XI of the Registrant's Declaration of Trust, filed as
       Exhibit 1(a) to Post-Effective Amendment No. 12 to the Registration
       Statement; and to Articles I, V and VI of Registrant's By-Laws, filed
       as Exhibit (2)(b) to Post-Effective Amendment No. 19 to the
       Registration Statement.
   (h) Incorporated by reference to Exhibit 6 to Post-Effective Amendment No.
       10 to the Registration Statement, filed on December 23, 1993.
   (i) Incorporated by reference to Exhibit 6(b) to Post-Effective Amendment
       No. 11 to the Registration Statement, filed on October 12, 1994.
   (j) Incorporated by reference to Exhibit 5 to Post-Effective Amendment No.
       12 to the registration statement on Form N-1A, filed on July 5, 2000,
       of Merrill Lynch Adjustable Rate Securities Fund, Inc. (File No.
       33-40332).
   (k) Incorporated by reference to Exhibit 9 to Pre-Effective Amendment No.1
       to the Registration Statement filed on August 21, 1984, and refiled
       with Post-Effective Amendment No. 12 on December 21, 1995 pursuant to
       EDGAR requirements.
   (l) Incorporated by reference to Exhibit 13 to Post-Effective Amendment No.
       14 to the Registration Statement on Form N-1A of Merrill Lynch
       Adjustable Rate Securities Fund, Inc. (File No. 33-40332), filed on
       September 28, 2000.
   (m) Incorporated by reference to Exhibit 14 to Post-Effective Amendment No.
       13 to the Registration Statement on Form N-1A of Merrill Lynch New York
       Municipal Bond Fund of Merrill Lynch Multi-State Municipal Series Trust
       filed on January 25, 1996.
   (n) Filed on July 24, 2002 as an Exhibit to the Registrant's Registration
       Statement on Form N-14 and incorporated herein by reference.
   (o) Included on the signature page of the Registrant's Registration
       Statement on Form N-14 filed on July 24, 2002 and incorporated herein
       by reference.




Item 17.  Undertakings.

     (1) The undersigned Registrant agrees that prior to any public reoffering
of the securities registered through use of a prospectus which is part of this
Registration Statement by any person or party who is deemed to be an
underwriter within the meaning of Rule 145(c) of the Securities Act of 1933,
as amended, the reoffering prospectus will contain information called for by
the applicable registration form for reofferings by persons who may be deemed
underwriters, in addition to the information called for by other items of the
applicable form.

     (2) The undersigned Registrant agrees that every prospectus that is filed
under paragraph (1) above will be filed as part of an amendment to the
registration statement and will not be used until the amendment is effective,
and that, in determining any liability under the Securities Act of 1933, as
amended, each post-effective amendment shall be deemed to be a new
registration statement for the securities offered therein, and the offering of
securities at that time shall be deemed to be the initial bona fide offering
of them.

     (3) The Registrant undertakes to file, by post-effective amendment, an
opinion of counsel as to certain tax matters, within a reasonable time after
receipt of such opinion.



                                  SIGNATURES

     As required by the Securities Act of 1933, this Registration Statement
has been signed on behalf of the Registrant, in the Township of Plainsboro and
State of New Jersey, on the 12th day of November, 2002.

                                   MERRILL LYNCH U.S. GOVERNMENT MORTGAGE FUND
                                                         (Registrant)


                                     By: /s/ Donald C. Burke
                                         --------------------------------------
                                        (Donald C. Burke, Vice President)

     As required by the Securities Act of 1933, this Registration Statement
has been signed by the following persons in the capacities and on the dates
indicated.



                  Signature                                    Title                               Date
                  ---------                                    -----                               ----
                                                                                
               Terry K. Glenn*                         President and Trustee
- -----------------------------------------------    (Principal Executive Officer)
               (Terry K. Glenn)

               Donald C. Burke*                     Vice President and Treasurer
- -----------------------------------------------         (Principal Financial
              (Donald C. Burke)                        and Accounting Officer)

              James H. Bodurtha*                              Trustee
- -----------------------------------------------
             (James H. Bodurtha)

                 Joe Grills*                                  Trustee
- -----------------------------------------------
                 (Joe Grills)

              Herbert I. London*                              Trustee
- -----------------------------------------------
             (Herbert I. London)

               Andre F. Perold*                               Trustee
- -----------------------------------------------
              (Andre F. Perold)

             Roberta Cooper Ramo*                             Trustee
- -----------------------------------------------
            (Roberta Cooper Ramo)

           Robert S. Salomon, Jr.*                            Trustee
- -----------------------------------------------
           (Robert S. Salomon, Jr.)

              Melvin R. Seiden*                               Trustee
- -----------------------------------------------
              (Melvin R. Seiden)

             Stephen B. Swensrud*                             Trustee
- -----------------------------------------------
            (Stephen B. Swensrud)

          * By: /s/ Donald C. Burke
- -----------------------------------------------
     (Donald C. Burke, Attorney-in-Fact)                                                  November 12, 2002




                                 EXHIBIT INDEX

(12) Opinion of Sidley Austin Brown & Wood LLP, tax counsel for the
     Registrant, as to the reorganization of Mercury U.S. Government
     Securities Fund, a series of The Asset Program, into the Registrant.