
<PAGE>
 
                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                 SCHEDULE 13D

                   Under the Securities Exchange Act of 1934

                         ACTUATE SOFTWARE CORPORATION
--------------------------------------------------------------------------------
                               (Name of Issuer)

                                 Common Stock
--------------------------------------------------------------------------------
                        (Title of Class of Securities)

                                   00508B102
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                                (CUSIP Number)

                             NICOLAS C. NIERENBERG
                       C/O ACTUATE SOFTWARE CORPORATION
                           999 BAKER WAY, SUITE 270
                             SAN MATEO, CA  94404
                                (650) 638-2000
(Name, Address and Telephone Number of Person Authorized to Receive Notices and
                                Communications)

                                 July 17, 1998
            (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition which is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), (f) or (g), check the following box. [_]

NOTE:  Schedules filed in paper format shall include a signed original and five
copies of the Schedule, including all exhibits.  See Rule 13d-1(A) for other
parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

                                      E-1
<PAGE>
 
                                 SCHEDULE 13D
-----------------------                                  
  CUSIP NO. 00508B102
-----------------------
 
------------------------------------------------------------------------------
 1    NAME OF REPORTING PERSON
      I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
                          
      Nicolas C. Nierenberg
------------------------------------------------------------------------------
 2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                      (a) [X] Not Applicable
                                                      (b) [_]
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 3    SEC USE ONLY
 
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 4    SOURCE OF FUNDS
      
      PF
------------------------------------------------------------------------------
 5    CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT 
      TO ITEMS 2(d) or (e) __
      N/A
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 6    CITIZENSHIP OR PLACE OF ORGANIZATION
      
       United States
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     NUMBER OF       7    SOLE VOTING POWER
      SHARES              1,500,000
   BENEFICIALLY           
     OWNED BY      -----------------------------------------------------------
       EACH          8    SHARED VOTING POWER
    REPORTING             0
      PERSON       -----------------------------------------------------------
       WITH          9    SOLE DISPOSITIVE POWER
                          1,500,000
                   -----------------------------------------------------------
                     10   SHARED DISPOSITIVE POWER
                          0
------------------------------------------------------------------------------
11    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      1,500,000
------------------------------------------------------------------------------
12    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*
      __ 
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13    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      10.9%
------------------------------------------------------------------------------
14    TYPE OF REPORTING PERSON*
      IN
------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
<PAGE>
 
                                 SCHEDULE 13D

Item 1.   Security and Issuer.
          ------------------- 

               This statement on Schedule 13D relates to the Common Stock of
Actuate Software Corporation, a Delaware corporation (the "Issuer").  The
principal executive offices of the Issuer are located at 999 Baker Way, Suite
270, San Mateo, California 94404.

Item 2.   Identity and Background.
          ----------------------- 

               (a)  This statement is filed by Nicolas C. Nierenberg (the
"Reporting Person").

               (b)  The address of the Reporting Person is c/o Actuate Software
Corporation, 999 Baker Way, Suite 270, Menlo Park, CA 94404.

               (c)  Present Principal Business or Employment:

                    1.  Chief Executive Officer of Issuer

                    2.  Chairman of the Board of Directors of Issuer

               (d) and (e)  During the last five years the Reporting Person has
not been (i) convicted in a criminal proceeding (excluding traffic violations or
similar misdemeanors) nor (ii) been a party to any civil proceeding of a
judicial or administrative body of competent jurisdiction, and is or was, as a
result of such proceeding, subject to a judgement, decree or final order
enjoining future violations of, or prohibiting or mandating activities subject
to, federal or state securities laws, or finding any violation with respect to
such laws.

               (f)  The Reporting Person is a citizen of the United States.

Item 3.   Source and Amount of Funds or Other Consideration.
          ------------------------------------------------- 

               Mr. Nierenberg purchased 1,350,000 shares of the Issuer for an
aggregate price of $135 pursuant to a Shareholders Agreement dated as of
November 24, 1993 by and between the Issuer and Mr. Nierenberg.  Mr. Nierenberg
purchased all shares of Common Stock of the Issuer with personal funds.

               Mr. Nierenberg acquired 150,000 options to purchase Common Stock
of the Issuer at a price of $0.62 per share pursuant to an Option Agreement
dated as of August 26, 1997 by and between the Issuer and Mr. Nierenberg.  This
option is exercisable within 60 days.

Item 4.   Purpose of Transaction.
          ---------------------- 
 
               At the time of acquiring the Common Stock and the option to
purchase Common Stock referenced herein, Mr. Nierenberg was, and currently is,
the Chief Executive Officer of the
<PAGE>
 
Issuer.  Mr. Nierenberg acquired the 1,350,000 shares of Common Stock in
connection with the initial capitalization of the Company and believes that his
holding or controlling a significant interest in the issuer assists in aligning
the interests of management and stockholders.

               Mr. Nierenberg may acquire, from time to time, additional shares
of the Common Stock or other securities of the Issuer in the open market, in
privately negotiated transactions, by exercise of options or otherwise.  Mr.
Nierenberg may, from time to time, retain or sell all or a portion of his
holdings of the shares of Common Stock in the open market or in privately
negotiated transactions.  Any action that Mr. Nierenberg might undertake will be
dependent upon his review of numerous factors, including, among other things,
the availability of shares of the Common Stock for purchase and the price levels
of such shares; general market and economic conditions; ongoing evaluation of
the Issuer's business operations and investment opportunities; the actions of
others in management and the Board of Directors of the Issuer; and other future
developments.  Although the foregoing reflects activities presently contemplated
Mr. Nierenberg with respect to the Issuer, the foregoing is subject to change at
any time.

               Other than as described above, Mr. Nierenberg does not have any
present plans or proposals which relate to or would result in: (i) the
acquisition by any person of additional securities of the Issuer; (ii) an
extraordinary corporate transaction, such as a merger, reorganization or
liquidation involving the Issuer; (iii) a sale or transfer of a material amount
of assets of the Issuer; (iv) any material change in the present capitalization
of dividend policy of the Issuer; (v) any other material change in the Issuer's
business or corporate structure; (vi) changes in the Issuer's certificate of
incorporation or by-laws or other actions which may impede the acquisition of
control or the Issuer by any persons; (vii) causing a class of securities of the
Issuer to be delisted from a national securities exchange or to cease to be
authorized to be quoted in an inter-dealer quotation system of a registered
national securities association; (viii) a class of equity securities of the
Issuer becoming eligible for termination of registration pursuant to Section 12
(g)(4) of the Securities Exchange Act of 1934, as amended; or (ix) any action
similar to those enumerated above.

Item 5.   Interest in Securities of the Issuer.
          ------------------------------------ 

               (a)  Mr. Nierenberg holds 1,350,000 shares of Common Stock and
options to purchase 150,000 shares of Common Stock collectively representing
approximately 10.9% of the outstanding Common Stock.

               (b)  Mr. Nierenberg has sole voting and dispositive power over
1,350,000 shares of Common Stock, representing approximately 9.8% of the
outstanding Common Stock.

               (c)  On December 11, 1998, Mr. Nierenberg was granted an option
to purchase 100,000 shares of Common Stock.

               (d)  No person other than the Reporting Person is known to the
Reporting Person to have the right to receive or the power to direct the receipt
of dividends from, or the proceeds from, the sale of the shares of Common Stock
of the Issuer owned by the respective Reporting Person.

               (e)  [Not Applicable]
<PAGE>
 
Item 6.   Contracts, Arrangements, Understandings or Relationships with Respect
          ---------------------------------------------------------------------
to Securities of the Issuer.
--------------------------- 

               (a)  On November 24, 1993, the Issuer and Mr. Nierenberg entered
into a Shareholders Agreement for the purchase of 1,500,000 shares of Common
Stock for an aggregate purchase price of $150. The foregoing summary of such
agreement is qualified in its entirety by reference to Exhibit 1 which is hereby
incorporated by reference.

               (b)  On August 26, 1997, the Issuer and Mr. Nierenberg entered
into an Option Agreement for an option to purchase 150,000 shares of Common
Stock at purchase price of $0.62 per share.  The foregoing summary of such
agreement is qualified in its entirety by reference to Exhibit 2 which is hereby
incorporated by reference.

               (c)  On December 11, 1998, the Issuer and Mr. Nierenberg entered
into an Option Agreement for an option to purchase 100,000 shares of Common
Stock at a purchase price of $14.125 per share. The foregoing summary of such
agreement is qualified in its entirety by reference to Exhibit 1 which is hereby
incorporated by reference.

Item 7.   Materials to be Filed as Exhibits.
          --------------------------------- 

               The following documents are included as exhibits:

               EXHIBIT 1  Share Purchase Agreement dated November 24, 1993 by
and between the Issuer and Nicolas C. Nierenberg.

               EXHIBIT 2  Notice of Grant of Stock Options and Option Agreement
dated August 26, 1997 by and between the Issuer and Nicolas C. Nierenberg.

               EXHIBIT 3  Notice of Grant of Stock Options and Option Agreement
dated December 11, 1998 by and between the Issuer and Nicolas C. Nierenberg.
<PAGE>
 
                                   SIGNATURE

          After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

Dated:  January 14, 1999

                                       NICOLAS C. NIERENBERG


                                       /s/ Nicolas C. Nierenberg
                                       -----------------------------------
                                       Nicolas C. Nierenberg
