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SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                     -------

                                    FORM 10-K

                        FOR ANNUAL AND TRANSITION REPORTS
                    PURSUANT TO SECTIONS 13 OR 15 (d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

(MARK ONE)

/X/ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES
    EXCHANGE ACT OF 1934

For the fiscal year ended MARCH 31, 2001.
                          --------------

                                       OR

/ / TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE
    SECURITIES EXCHANGE ACT OF 1934

For the transition period from ___________ to ___________

                         Commission file number 33-56254
                        MERRILL LYNCH MUNICIPAL ABS, INC.
           ----------------------------------------------------------
               (Exact Name of registrant as specified in charter)

        NEW YORK                                         13-369-8229
 ---------------------------------          -----------------------------------
(State or other jurisdiction of              (IRS Employer Identification No.)
 incorporation or organization)

WORLD FINANCIAL CENTER, NORTH TOWER, NINTH FLOOR, NEW YORK, NEW YORK    10281
--------------------------------------------------------------------  ----------
      (Address of principal executive offices)                        (Zip Code)

Registrant's telephone number, including area code (212) 449-7547
                                                   ----------------

Securities registered pursuant to Section 12 (b) of the Act:



<Table>
<Caption>
         TITLE OF EACH CLASS                             NAME OF EACH EXCHANGE ON WHICH REGISTERED
         -------------------                             -----------------------------------------
<S>                                                      <C>
PREREFUNDED MUNICIPAL CERTIFICATES, SERIES 1,            NEW YORK STOCK EXCHANGE
  DUE OCTOBER 1, 2012

PREREFUNDED MUNICIPAL CERTIFICATES, SERIES 2,            NEW YORK STOCK EXCHANGE
  DUE OCTOBER 1, 2012

PREREFUNDED MUNICIPAL CERTIFICATES, SERIES 3,            NEW YORK STOCK EXCHANGE
  DUE OCTOBER 1, 2012
</Table>


Securities registered pursuant to Section 12 (g) of the Act:

-------------------------------------------------------------------------
                                (Title of class)


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                                (Title of class)


                            {COVER PAGE 1 OF 2 PAGES}

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         Indicate by check mark whether the registrant: (1) has filed all
reports required to be filed by Section 13 or 15 (d) of the Securities Exchange
Act of 1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes /X/ No / /

         Indicate by check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K is not contained herein and will not be contained, to
the best of registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of the Form 10-K or any
amendment to this Form 10-K. /X/

         State the aggregate market value of the voting stock held by
non-affiliates of the registrant. The aggregate market value shall be computed
by reference to the price at which the stock was sold, or the average bid and
asked prices of such stock, as of a specified date within 60 days prior to the
date of filing. (See definition of affiliate in Rule 405).

         NOTE. If a determination as to whether a particular person or entity is
         an affiliate cannot be made without involving unreasonable effort and
         expense, the aggregate market value of the common stock held by
         non-affiliates may be calculated on the basis of assumptions reasonable
         under the circumstances, provided that the assumptions are set forth in
         this form.

         ALL THE VOTING STOCK IS HELD BY AFFILIATES OF THE REGISTRANT.

             (APPLICABLE ONLY TO REGISTRANTS INVOLVED IN BANKRUPTCY
                  PROCEEDINGS DURING THE PRECEDING FIVE YEARS)

         Indicate by check mark whether the registrant has filed all documents
and reports required to be filed by Section 12, 13 or 15 (d) of the Securities
Exchange Act of 1934 subsequent to the distribution of securities under a plan
confirmed by a court. Yes / / No / /

                   (APPLICABLE ONLY TO CORPORATE REGISTRANTS)

         Indicate the number of shares outstanding of each of the registrant's
classes of common stock, as of the latest practicable date.

         AS OF MARCH 31, 2001, THERE ARE 100 SHARES OF COMMON STOCK.

                       DOCUMENTS INCORPORATED BY REFERENCE

         List hereunder the following documents if incorporated by reference and
the Part of the Form 10-K (e.g., Part I, Part II, etc.) into which the document
is incorporated: (1) any annual report to security-holders; (2) any proxy or
information statement; and (3) any prospectus filed pursuant to Rule 424 (b) or
(c) under the Securities Act of 1933. The listed documents should be clearly
described for identification purposes (e.g., annual report to security-holders
for fiscal year ended December 24, 1980).


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PART I

Item 1.           BUSINESS.
                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 2.           PROPERTIES.
                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 3.           LEGAL PROCEEDINGS.
                  NONE.

Item 4.           SUBMISSION OF MATTERS TO A VOTE OF SECURITY-HOLDERS.
                  NONE.

                                     PART II

Item 5.           MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDERS
                  MATTERS.

                  (a)  Number of holders of record of each Series of
         Certificates as of March 31, 2001: SERIES 1: 33 HOLDERS*;
                                            SERIES 2: 29 HOLDERS*;
                                            SERIES 3: 61 HOLDERS*.

                  (b) Principal market in which registrant's Certificates are
         being traded:

                           SERIES 1:                 OVER THE COUNTER
                           SERIES 2:                 OVER THE COUNTER
                           SERIES 3:                 OVER THE COUNTER

                  (c) Report of Dividends:

                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 6.           SELECTED FINANCIAL DATA.
                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 7.           MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                  AND RESULTS OF OPERATIONS.

                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 8.           FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

                  EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 9.           CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                  AND FINANCIAL DISCLOSURE.

                  NONE.


--------
* Number of Holders per Series equals the number of Direct Participants holding
Certificates through The Depository Trust Company plus the number of accounts
held at Merrill Lynch for the benefit of Certificateholders.


                                        3
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                                    PART III

Item 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.
         EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 11. EXECUTIVE COMPENSATION.
         EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT.
         EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.

Item 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.
         EXEMPT PER NO-ACTION LETTER PUBLICLY AVAILABLE MAY 30, 1996.



SUPPLEMENTAL INFORMATION.

                  (a) Annual Report
                  NONE.

                  (b) Proxy Statement
                  NONE.


                                        4

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                                   SIGNATURES

         Pursuant to the requirements of the Section 13 or 15 (d) of the
Securities Exchange Act of 1934, the registrant has duly caused this report to
be signed on its behalf by the undersigned, thereunto duly authorized.

                                    MERRILL LYNCH MUNICIPAL ABS, INC.

                                    By:
                                          ----------------------------------
                                    Name:   Edward J. Sisk
                                    Title:  Authorized Signatory
                                    Date:   March 31, 2001


                                        5

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                                  EXHIBIT INDEX

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<Caption>
EXHIBIT                                                                                    PAGE
-------                                                                                    ----
<S>                                                                                        <C>
 99.1     Independant Accountants' Report on Applying Agreed-Upon
          Procedures                                                                          7

 99.2     Notice of Substitution of Defeasance Obligations                                   11

 99.3     Statements to holders of Merrill Lynch Municipal ABS, Inc. Prerefunded
          Municipal Certificates, Series 1, Series 2, Series 3 relating to the
          Distribution Dates of April 1, 2000, as amended, and October 1, 2000.              12
</Table>