As filed with the Securities and Exchange Commission on October 31, 2002
                                             Securities Act File No. 333-83092
                                     Investment Company Act File No. 811-09637
==============================================================================

                    U.S. SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

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

                                   FORM N-14
                            REGISTRATION STATEMENT
                                     UNDER
                          THE SECURITIES ACT OF 1933

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

                          Pre-Effective Amendment No.                     /   /
                        Post-Effective Amendment No. 1                    / X /
                       (Check appropriate box or boxes)

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

                  Merrill Lynch Large Cap Series Funds, Inc.
            (Exact Name of Registrant as Specified in its Charter)

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

                                (609) 282-2800
                       (Area Code and Telephone Number)

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

                            800 Scudders Mill Road
                         Plainsboro, New Jersey 08536
 (Address of Principal Executive Offices: Number, Street, City, State, Zip Code)

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

                                Terry K. Glenn
                  Merrill Lynch Large Cap Series Funds, Inc.
             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:

     Counsel for the Fund:
      Frank P. Bruno, Esq.                            Philip L. Kirstein
SIDLEY, AUSTIN, BROWN & WOOD LLP                 FUND ASSET MANAGEMENT, L.P.
       787 Seventh Avenue                               P.O. Box 9011
    New York, New York 10019                  Princeton, New Jersey 08543-9011

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

     Title of Securities Being Registered: Common Stock, Par Value $.10 per
share.

     No filing fee is required because of reliance on Section 24(f) under the
Investment Company Act of 1940, as amended.


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





     This Post-Effective Amendment No. 1 to the Registrant's Registration
Statement on Form N-14 (File No. 333-83092) (the "N-14 Registration
Statement") consists of the following:

(1)  Facing Sheet of the N-14 Registration Statement.

(2)  Part C of the N-14 Registration Statement (including signature pages).

     Parts A and B are incorporated herein by reference from the Registrant's
Proxy Statement and Prospectus filed on March 27, 2002 under 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 in order to file as Exhibit 12 to the N-14 Registration Statement,
the tax opinion of Sidley Austin Brown & Wood LLP, tax counsel for the
Registrant, and to file as Exhibit 16 to the N-14 Registration Statement, a
power of attorney executed by each of the current members of the Registrant's
Board of Directors. The tax opinion relates to the reorganization of Mercury
U.S. Large Cap Fund, a series of Mercury Funds, Inc., and Merrill Lynch Large
Cap Core Fund, a series of the Registrant.


                                      2





                                    PART C
                               OTHER INFORMATION

Item 15.  Indemnification.

     Reference is made to Article VI of the Registrant's Articles of
Incorporation, Article VI of the Registrant's By-Laws, Section 2-418 of the
Maryland General Corporation Law and Section 9 of the Distribution Agreement.

     Insofar as the conditional advancing of indemnification moneys for
actions based on the Investment Company Act of 1940, as amended (the
"Investment Company Act"), may be concerned, Article VI of the Registrant's
By-Laws provides that such payments will be made only on the following
conditions: (i) advances may be made only on receipt of a written affirmation
of such person's good faith belief that the standard of conduct necessary for
indemnification has been met and a written undertaking to repay any such
advance if it is ultimately determined that the standard of conduct has not
been met; and (ii) (a) such promise must be secured by a security for the
undertaking in form and amount acceptable to the Registrant, (b) the
Registrant is insured against losses arising by receipt of the advance, or (c)
a majority of a quorum of the Registrant's disinterested non-party Directors,
or an independent legal counsel in a written opinion, shall determine, based
upon a review of readily available facts, that at the time the advance is
proposed to be made, there is reason to believe that the person seeking
indemnification will ultimately be found to be entitled to indemnification.

     In Section 9 of the Distribution Agreement relating to the securities
being offered hereby, the Registrant agrees to indemnify FAM Distributors, Inc.
(the "Distributor") and each person, if any, who controls the Distributor
within the meaning of the Securities Act of 1933, as amended (the "Securities
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 Securities
Act may be permitted to Directors, 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 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 and the principal underwriter
in connection with the successful defense of any action, suit or proceeding)
is asserted by such Director, 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 Securities Act and will be governed by the final adjudication
of such issue.

Item 16.  Exhibits.


          
   1     --      Articles of Incorporation of the Registrant, filed October 20, 1999.(a)
   2     --      By-Laws of the Registrant.(a)
   3     --      Not applicable.
   4     --      Form of Agreement and Plan of Reorganization among (i) the Registrant, on behalf of Merrill Lynch Large Cap Core
                 Fund, (ii) Mercury Funds, Inc., on behalf of Mercury U.S. Large Cap Fund, (iii) Master Large Cap Series Trust, on
                 behalf of Master Large Cap Core Portfolio and (iv) Mercury Master Trust, on behalf of Mercury Master U.S. Large Cap
                 Portfolio.(f)


                                                                 C-1





   5     --      Portions of the Articles of  Incorporation  and By-Laws of the  Registrant  defining the rights of holders of
                 shares of common stock of the Registrant.(b)
   6     --      None.
   7     --      Form of Unified Distribution Agreement between the Registrant and FAM Distributors, Inc. (the "Distributor").(d)
   8     --      None.
   9     --      None.
   10(a) --      Form of Unified Class B Distribution Plan of the Registrant.(e)
   10(b) --      Form of Unified Class C Distribution Plan of the Registrant.(e)
   10(c) --      Form of Unified Class D Distribution Plan of the Registrant.(e)
   10(d) --      Merrill Lynch Select PricingSM System Plan pursuant to Rule 18f-3.(c)
   11    --      Opinion and Consent of Sidley Austin Brown & Wood LLP, counsel for the Registrant.(g)
   12    --      Tax Opinion of Sidley Austin Brown and Wood LLP.(h)
   13    --      Not applicable.
   14(a) --      Consent of Deloitte & Touche LLP, independent auditors for the Registrant.(g)
   14(b) --      Consent of Deloitte & Touche LLP, independent auditors for Mercury Funds, Inc.(g)
   15    --      Not applicable.
   16    --      Power of Attorney.(h)
   17(a) --      Prospectus, dated January 14, 2002, of the Registrant.(g)
   17(b) --      Statement of Additional Information, dated January 14, 2002, of the Registrant.(g)
   17(c) --      Prospectus, dated September 14, 2001, of Mercury U.S. Large Cap Fund.(g)
   17(d) --      Statement of Additional Information, dated September 14, 2001, of Mercury U.S. Large Cap Fund.(g)
   17(e) --      Annual Report to Stockholders of the Registrant for the fiscal year ended October 31, 2001.(g)
   17(f) --      Annual Report to Stockholders of Mercury U.S. Large Cap Fund for the fiscal year ended May 31, 2001.(g)
   17(g) --      Semi-Annual Report to Stockholders of Mercury U.S. Large Cap Fund for the six-month period ended November 30,
                 2001.(g)
   17(h) --      Form of Proxy Card.(g)


- --------------
(a)  Filed on October 20, 1999 as an Exhibit to the Registrant's Registration
     Statement on Form N-lA under the Securities Act of 1933, as amended (File
     No. 333-89389) (the "N-lA Registration Statement").
(b)  Reference is made to Article II, Article IV, Article V (sections 2, 3, 4,
     6, 7 and 8), Article VI, Article VII and Article IX of the Registrant's
     Articles of Incorporation, filed as Exhibit (1) to the N-lA Registration
     Statement, and to Article II, Article III (sections 1, 3, 5, 6 and 17),
     Article VI, Article VII, Article XII, Article XIII and Article XIV of the
     Registrant's By-Laws filed as Exhibit (2) to the N-lA Registration
     Statement.
(c)  Filed on December 22, 1999 as an Exhibit to Pre-Effective Amendment No. 1
     to the Registration Statement.
(d)  Incorporated by reference to Exhibit 5 to the Registration Statement on
     Form N-lA of Merrill Lynch Mid Cap Growth Fund, Inc. (File No.
     811-10025), filed on July 21, 2000.
(e)  Incorporated by reference to Exhibit 13 to the Registration Statement on
     Form N-1A of Merrill Lynch Mid Cap Growth Fund, Inc. (File No.
     811-10025), filed on July 21, 2000.
(f)  Included as Exhibit I to the Proxy Statement and Prospectus contained in
     this Registration Statement.
(g)  Filed on February 20, 2002 as an Exhibit to the Registrant's N-14
     Registration Statement.
(h)  Filed herewith.


                                     C-2





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 party 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.


                                     C-3





                                  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 30th day of October, 2002.

                                 MERRILL LYNCH LARGE CAP SERIES FUNDS, INC.
                                 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 date
indicated.



SIGNATURES                        TITLE                                       DATE
- ----------                        -----                                       ----
                                                                       
     TERRY K. GLENN*              President (Principal Executive
- -------------------------         Officer) and Director
    (Terry K. Glenn)

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

   JAMES H. BODURTHA*             Director
- -------------------------
   (James H. Bodurtha)

       JOE GRILLS*                Director
- --------------------------
      (Joe Grills)

   HERBERT I. LONDON*             Director
- --------------------------
   (Herbert I. London)

    ANDRE F. PEROLD*              Director
- --------------------------
    (Andre F. Perold)

  ROBERTA COOPER RAMO*            Director
- --------------------------
  (Roberta Cooper Ramo)

 ROBERT S. SALOMON, JR.*          Director
- --------------------------
(Robert S. Salomon, Jr.)

    MELVIN R. SEIDEN*             Director
- --------------------------
   (Melvin R. Seiden)

  STEPHEN B. SWENSRUD*            Director
- --------------------------
  (Stephen B. Swensrud)

*By:  /s/ DONALD C. BURKE                                                     October 30, 2002
    ----------------------
(Donald C. Burke, Attorney-in-
Fact)



                                     C-4





Master Large Cap Series Trust has duly caused this Registration Statement of
Merrill Lynch Large Cap Series Funds, Inc. to be signed on its behalf by the
undersigned, thereunto duly authorized, in the Township of Plainsboro and
State of New Jersey, on the 30th day of October, 2002.

                                          MASTER LARGE CAP SERIES TRUST
                                                   (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 date
indicated.



SIGNATURES                        TITLE                                       DATE
- ----------                        -----                                       ----
                                                                       
     TERRY K. GLENN*              President (Principal Executive Officer)
- -------------------------         and Trustee
    (Terry K. Glenn)

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

   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                                                    October 30, 2002
    ----------------------
(Donald C. Burke, Attorney-in-
Fact)



                                     C-5





                                 EXHIBIT INDEX

Exhibit
Number         Description
- ------         -----------

12       --    Tax opinion of Sidley Austin Brown & Wood LLP, tax counsel for
               the Registrant.
16       --    Power of Attorney


                                     C-6