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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------

                                  FORM 10-K/A
                                AMENDMENT NO. 1

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

                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000

                                       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: 000-26789

                            BROADBASE SOFTWARE, INC.
           (EXACT NAME OF THE REGISTRANT AS SPECIFIED IN ITS CHARTER)

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<S>                                            <C>
                   DELAWARE                                      77-0417081
(STATE OR OTHER JURISDICTION OF INCORPORATION)      (I.R.S. EMPLOYER IDENTIFICATION NO.)

            181 CONSTITUTION DRIVE
             MENLO PARK, CA 94025                              (650) 614-8300
   (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)         (THE REGISTRANT'S TELEPHONE NUMBER)
</TABLE>

        SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT: NONE

          SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:
                    COMMON STOCK, $.001 PAR VALUE PER SHARE

     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 the Registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K.  [ ]

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<CAPTION>
                                                                  AS OF
                                                              MARCH 1, 2001
                                                              --------------
<S>                                                           <C>
Aggregate market value of the voting and nonvoting common
  equity held by non-affiliates of the Registrant, based the
  closing sale price of such stock*.........................   $259,087,281
                                                               ------------
Number of shares of common stock outstanding................     81,793,920
                                                               ------------
</TABLE>

---------------
* Shares of common stock held by each executive, director and 10% or greater
  shareholder have been excluded in that such persons may be deemed affiliates.
  This determination of affiliate status is not necessarily a conclusive
  determination for other purposes.

                      DOCUMENTS INCORPORATED BY REFERENCE

     No documents are incorporated by reference into this report.

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                            BROADBASE SOFTWARE, INC.

                             AMENDMENT NO. 1 TO THE
                        2000 ANNUAL REPORT ON FORM 10-K

                               TABLE OF CONTENTS

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<S>       <C>                                                           <C>
PART III
Item 10.  Directors and Executive Officers of the Registrant..........   1
          Signatures..................................................   4
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EXPLANATORY NOTE: This Form 10-K/A amends Broadbase Software, Inc.'s Annual
Report on Form 10-K for the fiscal year ended December 31, 2000. The purpose of
this report is to provide the information required to be set forth in "Item 10.
Compliance under Section 16(a) of the Securities Exchange Act of 1934" of Part
III of Broadbase's Annual Report.

                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

     The following table shows the name, age and position of each of our
executive officers and directors as of March 1, 2001:

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<CAPTION>
            NAME              AGE                    PRINCIPAL OCCUPATION
            ----              ---                    --------------------
<S>                           <C>   <C>
Chuck Bay...................  43    Chairman of the Board, Chief Executive Officer and
                                    President
Rusty Thomas................  40    Executive Vice President and Chief Financial Officer
Fabio Angelillis............  40    Executive Vice President, Engineering
Thomas Doyle................  50    Chief Operating Officer and Executive Vice President
                                    of Sales
Brian Kelly.................  35    Executive Vice President of Products
Chris Maeda.................  34    Executive Vice President and Chief Technology Officer
David Milam.................  45    Executive Vice President, Marketing
Greg Martin.................  36    Senior Vice President, Consulting and Customer
                                    Advocacy
Eric Willgohs...............  35    General Counsel, Vice President Legal and Secretary
Robert Davoli...............  52    Director
Kevin Harvey................  36    Director
Massood Zarrabian...........  52    Director and President E-Services Division of
                                    Broadbase
</TABLE>

     CHUCK BAY joined Broadbase in January 1998 and currently serves as Chairman
of the Board, Chief Executive Officer and President of Broadbase. Mr. Bay
previously served as our Chief Financial Officer, General Counsel and Executive
Vice President of Operations. From July 1997 to January 1998, he served as Chief
Financial Officer and General Counsel for Reasoning, Inc., a software company.
From January 1995 to August 1997, he served as Chief Financial Officer and
General Counsel, for Pure Atria Software, Inc., a software company. Mr. Bay
holds a B.S. degree in business administration from Illinois State University
and a J.D. degree from the University of Illinois.

     RUSTY THOMAS has served as Executive Vice President and Chief Financial
Officer since joining Broadbase in January 2000. From June 1982 to July 1995 and
from April 1998 to January 2000, Mr. Thomas held various positions in the high
technology practice of KPMG LLP, including 8 years as a partner in the Silicon
Valley office and most recently as an Industry Leader for Electronics and
Software segments. From July 1995 to April 1998, he served as a Vice President
in the finance department of Rubbermaid Inc., a consumer products company. Mr.
Thomas holds a B.S. degree in business administration from Creighton University.

     FABIO ANGELILLIS has served as Executive Vice President, Engineering since
joining Broadbase in September 2000. From October 1990 to September 2000, Mr.
Angelillis held various management positions, including Vice President of
Research and Development and Operations, at Cadence Design Systems, Inc. a
provider of electronic design automation software. From January 1998 to October
1990, he served as Engineering Manager at Teradyne, Inc., a manufacturer of
automatic test equipment and related software for the electronics and
communications industries. From May 1985 to January 1988, he served as Software
Engineer at Hewlett-Packard Company, a provider of computing and imaging
solutions and services. Mr. Angelillis holds a B.S. degree in computer
engineering from the University of Florida.

                                        1
<PAGE>   4

     THOMAS DOYLE joined Broadbase in April 1999 in the capacity of Executive
Vice President of Sales and currently serves as Chief Operating Officer and
Executive Vice President of Sales. From October 1996 to April 1999, Mr. Doyle
served as Senior Vice President of Worldwide Sales at Reasoning, Inc. From May
1984 to September 1996, he held various sales and sales management positions at
Tandem Computers Incorporated, a provider of computer systems and client/server
solutions. Mr. Doyle holds a B.S. degree in finance from the University of
Missouri.

     BRIAN KELLY joined Broadbase in December 1998 and currently serves as
Executive Vice President of Products. Mr. Kelly previously served as our
Executive Vice President of Applications and Engineering. From June 1998 to
December 1998, he served as Director of Product Strategy, Analytic Applications
at PeopleSoft, Inc., a provider of enterprise software and services. From June
1996 to June 1998, he served as Vice President of Product Strategy at Intrepid
Systems, Inc., a software company. From December 1992 to June 1996, he served as
President of Kelly Information Systems, a software company. Mr. Kelly holds a
B.S. degree in computer science from the University of Cincinnati.

     CHRIS MAEDA joined Broadbase in February 2000 and currently serves as
Executive Vice President and Chief Technology Officer. From March 1997 until its
acquisition by Broadbase in February 2000, Dr. Maeda served as Chief Technology
Officer of Rubric, Inc., a provider of e-marketing software applications, which
he co-founded. From May 1995 to February 1997, he held various positions at the
Xerox Palo Alto Research Center. Dr. Maeda holds a B.S. degree in computer
science from the Massachusetts Institute of Technology, and M.S. and Ph.D.
degrees in computer science from Carnegie Mellon University.

     DAVID MILAM has served as Executive Vice President, Marketing since joining
Broadbase in April 2000. From 1995 to April 2000, he served as Vice President,
Full Custom IC Design Services, Vice President of Product Marketing, and Vice
President Methodology Services Marketing of Cadence Design Systems, Inc. From
1989 to 1995, he served as Director Product Marketing and European Marketing
Director at Structural Dynamics Research Corporation, a provider of software
solutions for collaborative product development. From 1984 to 1989, he served as
Director of Market Development and Director of Distribution Programs of Cimlic
Corporation, a design and document automation software company. Mr. Milam holds
a B.S. degree in Financial Management and Quantitative Systems and an M.B.A.
degree, both from California State University at Long Beach.

     GREG MARTIN has served as Senior Vice President, Consulting and Customer
Advocacy since joining Broadbase in January 2000. From December 1988 to January
2000, Mr. Martin held various positions in the high technology practice of KPMG
LLP, including partner and Industry Leader for Customer Relationship and
eBusiness Solution Integration. Mr. Martin holds a B.S. degree in chemistry from
the State University of New York.

     ERIC WILLGOHS joined Broadbase in July 1999 and currently serves as General
Counsel, Vice President Legal and Secretary. From September 1997 to July 1999,
Mr. Willgohs held various positions with Reasoning, Inc., most recently as
General Counsel. From July 1993 to July 1997, Mr. Willgohs held various
positions with Pure Atria Software, Inc., most recently as Associate General
Counsel. Mr. Willgohs holds a B.S. degree in electrical engineering from
Vanderbilt University and a J.D. degree from Stanford University.

     ROBERT DAVOLI has served as a member of our board of directors since
December 2000. From March 1998 until its acquisition by Broadbase in December
2000, he was a director of Servicesoft. Since January 1995, Mr. Davoli has also
been a Managing Director of Sigma Partners, a venture capital firm. He is also a
director of Vignette Corporation, Versata, Inc., ISS Group, Inc., Storage
Networks and several privately held companies. Mr. Davoli holds a B.A. degree in
History from Ricker College.

     KEVIN HARVEY has served as a member of our board of directors since January
1996. Mr. Harvey has been a managing member of Benchmark Capital, a venture
capital firm, since it was founded in January 1995. Mr. Harvey is also a
director of Red Hat Software, a developer and provider of open source software
and services, Ashford.com, an Internet retailer, Critical Path, an e-mail
hosting services company and several privately held companies. Mr. Harvey holds
a B.S. degree in electrical engineering from Rice University.

                                        2
<PAGE>   5

     MASSOOD ZARRABIAN has served as a member of our board of directors, and as
an employee of Broadbase in the position of President, E-Service Division, since
joining us in December 2000. From July 1999 until its acquisition by Broadbase
in December 2000, he held various positions with Servicesoft, a customer
relationship management software company, including most recently as Chief
Executive Officer, President and a director. From January 1999 to July 1999, he
served as Vice President of Product Operations, and from October 1998 to January
1999 as Vice President of Product Development, at Lewtan Technologies, Inc., a
software company specializing in securitized transactions. From July 1997 to
October 1998, held various positions with Cayenne Software, Inc., a case tools
company, including most recently as Executive Vice President and Chief Operating
Officer. From February 1994 to July 1996, he held the positions of Vice
President, Research and Development and Vice President, Product Operations at
Cayenne's predecessor company, Bachman Information Systems. Mr. Zarrabian holds
a B.S. degree in civil engineering from the Massachusetts Institute of
Technology.

COMPLIANCE UNDER SECTION 16(a) OF THE SECURITIES EXCHANGE ACT OF 1934

     Section 16 of the Securities Exchange Act of 1934, as amended, requires our
directors and officers, and persons who own more than 10% of our common stock to
file initial reports of ownership and reports of changes in ownership with the
Securities and Exchange Commission and the Nasdaq National Market. Such persons
are required by Securities and Exchange Commission regulations to furnish us
with copies of all Section 16(a) forms that they file.

     Based solely on our review of the copies of such forms furnished to us and
written representations from our executive officers and directors, we believe
that Fabio Angelillis, Chris Maeda, Greg Martin, David Milam, Hal Steger, Rusty
Thomas and Eric Willgohs each filed a Form 3 late during the year ended December
31, 2000. Other than those persons and filings previously listed, we believe
that all other Section 16(a) filing requirements for the year ended December 31,
2000 were met.

                                        3
<PAGE>   6

                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15 (d) 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, on this 30th day of
April, 2001.

                                         BROADBASE SOFTWARE, INC.

                                         By:       /s/ ERIC WILLGOHS
                                           -------------------------------------
                                           Eric Willgohs
                                           General Counsel, Vice President Legal
                                             and Secretary

                               POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Chuck Bay and Eric Willgohs, jointly and
severally, his attorney in fact, each with the full power of substitution, for
such person, in any and all capacities, to sign any and all amendments to this
Annual Report on Form 10-K, and to file the same, with all exhibits thereto and
other documents in connection therewith, with the Securities and Exchange
Commission, granting unto said attorney-in-fact and agent full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in connection therewith, as fully to all intents and purposes as he
might do or could do in person hereby ratifying and confirming all that each of
said attorneys-in-fact and agents, or his substitute, may do or cause to be done
by virtue hereof.

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the dates indicated:

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<CAPTION>
                        NAME                                         TITLE                    DATE
                        ----                                         -----                    ----
<S>                                                    <C>                               <C>
            PRINCIPAL EXECUTIVE OFFICER:

                          *                                Chief Executive Officer,      April 30, 2001
-----------------------------------------------------    President and Chairman of the
                      Chuck Bay                                Board of Directors

           PRINCIPAL FINANCIAL OFFICER AND
            PRINCIPAL ACCOUNTING OFFICER:

                    /s/ SAM HENRY                        Executive Vice President and    April 30, 2001
-----------------------------------------------------       Chief Financial Officer
                      Sam Henry

                     DIRECTORS:

                          *                                        Director              April 30, 2001
-----------------------------------------------------
                    Robert Davoli

                          *                                        Director              April 30, 2001
-----------------------------------------------------
                    Kevin Harvey

                          *                                        Director              April 30, 2001
-----------------------------------------------------
                  Massood Zarrabian

               * By: /s/ ERIC WILLGOHS                         Attorney-in-fact          April 30, 2001
       --------------------------------------
                    Eric Willgohs
</TABLE>

                                        4