<PAGE>



     As filed with the Securities and Exchange Commission on August 31, 2000
                                          Registration No. 333 - ___________
============================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   -----------
                                    FORM S-8

             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

-------------------------------------------------------------------------------
                               AVANT! CORPORATION
             (Exact Name of Registrant as Specified on Its Charter)

                 DELAWARE                           94-3133226
-------------------------------------------------------------------------------
       (State or Other Jurisdiction      (I.R.S. Employer Identification No.)
              of Incorporation                   or Organization)

                              46871 Bayside Parkway
                                Fremont, CA 94538
              (Address of Principal Executive Offices and Zip Code)

                                   -----------
                      2000 STOCK OPTION/STOCK ISSUANCE PLAN
                          EMPLOYEE STOCK PURCHASE PLAN
                              (Full title of plans)

                                  Gerald C. Hsu
                      President and Chief Executive Officer
                              46871 Bayside Parkway
                                Fremont, CA 94538
                                 (510) 413-8000
                    (Name and Address, and Telephone Number,
                   Including Area Code, of Agent For Service)

                                   -----------
                                    Copy to:
                               Susan Thorner, Esq.
                              Phyllis Solomon, Esq.
                           Farella Braun & Martel LLP
                              235 Montgomery Street
                          San Francisco, CA 94104-3159


<PAGE>


                         Calculation of Registration Fee

<TABLE>
<CAPTION>

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

Title of securities to be registered       Amount to be         Proposed              Proposed maximum     Amount of
                                           registered(1)        maximum offering      aggregate offering   registration fee(3)
                                                                price per share(2)    price(2)
------------------------------------------ -------------------- --------------------- -------------------- ------------------

<S>                                         <C>                 <C>                   <C>                  <C>
2000 Stock Option/Stock Issuance Plan       2,500,000 shares         $14.03125        $35,078,125              $9,260.63
Common Stock (par value $.001)

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

</TABLE>

----------------
(1)Pursuant to Rule 416(a), also covers additional securities that may be
offered as a result of stock splits, stock dividends or similar transactions.

(2)Estimated pursuant to Rule 457(h) solely for purposes of determining the
registration fee of $9,260.63, which represents the average of the high and low
prices of the Common Stock reported on the Nasdaq Stock Market on August 28,
2000.

(3)Calculated pursuant to Rule 457(c) on the basis of the average of the high
and low prices of the Common Stock reported on the Nasdaq Stock Market on
August 28, 2000.



                                       2
<PAGE>

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

         The Company hereby incorporates by reference in this Registration
Statement the following documents:

         a. The Company's Annual Report on Form 10-K for the fiscal year ended
            December 31, 1999;

         b. The Company's Quarterly Report on Form 10-Q for the calendar quarter
            ended March 31, 2000;

         c. The Company's Quarterly Report on Form 10-Q for the calendar quarter
            ended June 30, 2000;

         d. All other reports filed pursuant to Section 13(a) or 15(d) of the
            Securities Exchange Act of 1934, as amended (the "1934 Act") since
            December 31, 1999; and

         e. The description of the Company's capital stock contained in the
            Company's Registration Statement No. 0-25864 on Form 8-A filed with
            the Securities and Exchange Commission (the "Commission") on April
            12, 2000 pursuant to Section 12 of the 1934 Act, including any
            amendment or report filed for the purpose of updating such
            description.

         All documents subsequently filed by the Company pursuant to Section
13(a), 13(c), 14 or 15(d) of the 1934 Act prior to the filing of a
post-effective amendment which indicates that all securities offered have been
sold or which deregisters all securities then remaining unsold, also shall be
deemed to be incorporated by reference in this Registration Statement and to be
part hereof from the date of the filing of such documents.

ITEM 4. DESCRIPTION OF SECURITIES

                  Not Applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

                  Not Applicable.




                                       3
<PAGE>


ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

         Section 145 of the Delaware General Corporation Law authorizes a court
to award or a corporation's Board of Directors to grant indemnification to
directors and officers in terms sufficiently broad to permit such
indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the Securities Act of 1933,
as amended (the "1933 Act"). The Company's Bylaws provide for indemnification of
its directors, officers, employees and other agents to the maximum extent
permitted by the Delaware General Corporation Law. The Company's Certificate of
Incorporation provides that, pursuant to Delaware law, its directors shall not
be liable for monetary damages for breach of their fiduciary duty as directors
to the Company and its stockholders. This provision in the Certificate of
Incorporation does not eliminate the fiduciary duty of the directors, and, in
appropriate circumstances, equitable remedies such as injunctive or other forms
of non-monetary relief will remain available under Delaware law. In addition,
each director will continue to be subject to liability for breach of the
director's duty of loyalty to the Company for acts or omissions not in good
faith or involving intentional misconduct, for knowing violations of law, for
actions leading to improper personal benefit to the director and for payment of
dividends or approval of stock repurchases or redemptions that are unlawful
under Delaware law. The provision also does not affect a director's
responsibilities under any other law, such as the federal securities laws or
state or federal environmental laws. The Company has entered into
Indemnification Agreements with its officers and directors. The Indemnification
Agreements provide the Company's officers and directors with further
indemnification to the maximum extent permitted by the Delaware General
Corporation Law.

         The Company also maintains insurance policies which insure the
directors and officers of the Company against certain liabilities including
claims arising out of alleged wrongful acts by such persons in their respective
capacities as directors and officers of the Company, subject to certain
exceptions.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

                  Not Applicable.


                                       4
<PAGE>


ITEM 8. EXHIBITS.

<TABLE>


               <S>        <C>

                  3.1      Restated Certificate of Incorporation of the Company, as amended to date(1)

                  3.2      Amended and Restated Bylaws of the Company(2)

                  4.1      Rights Plan dated September 4, 1998 between the Registrant and Harris Trust Company of
                           California(3)

                  5        Opinion and consent of Farella Braun & Martel LLP
                           regarding the legality of the securities being
                           registered

                 23.1      Consent of Independent Auditors

                 23.2      Consent of Farella Braun & Martel LLP (included in Exhibit 5)

                 24        Power of attorney (included in signature page hereof)

</TABLE>

ITEM 9. UNDERTAKINGS.

         The undersigned Registrant hereby undertakes:

         (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this Registration Statement:

                  (i)  To include any prospectus required by
         Section 10(a)(3) of the 1933 Act;

                  (ii) To reflect in the prospectus any facts or events arising
         after the effective date of this Registration Statement (or the most
         recent post-effective amendment hereof) which, individually or in the
         aggregate, represent a fundamental change in the information set forth
         in this Registration Statement. Notwithstanding the foregoing, any
         increase or decrease in volume of securities offered (if the total
         dollar value of securities offered would not exceed that which was
         registered) and any deviation from the low or high and of the estimated
         maximum offering range may be reflected in the form of prospectus filed
         with the Commission pursuant to Rule 424(b) if, in the aggregate, the
         changes in volume and price represent no more than 20 percent change in
         the maximum



--------

(1)Incorporated by reference from the Company's Registration Statement on Form
S-3A (File No. 333-67629) as declared effective on January 22, 1999.

(2)Incorporated by reference from the Company's Current Report on Form 8-K filed
with the Commission on September 18, 1998.

(3)Incorporated by reference from the Company's Registration Statement on
Form 8-A12G filed with the Commission on September 18, 1998.


                                       5
<PAGE>


         aggregate offering price set forth in the "Calculation of
         Registration Fee" table in the effective registration statement.

                  (iii) To include any material information with respect to the
         plan of distribution not previously disclosed in this Registration
         Statement or any material change to such information in this
         Registration Statement;

         provided, however, that paragraphs (i) and (ii) do not apply if the
information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed with or furnished to the
Commission by the Company pursuant to Section 13 or Section 15(d) of the 1934
Act that are incorporated by reference in this Registration Statement.

         (2) That, for the purpose of determining any liability under the 1933
Act, each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities offered herein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof.

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

         The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the 1933 Act, each filing of the Company's
Annual Report pursuant to Section 13(a) or Section 15(d) of the 1934 Act (and,
where applicable, each filing of an employee benefit plan's annual report
pursuant to Section 15(d) of the 1934 Act) that is incorporated by reference
into this Registration Statement shall be deemed to be a new registration
statement relating to the securities offered herein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof.

   Insofar as indemnification for liabilities arising under the 1933 Act may be
permitted to directors, officers and controlling persons of the Company pursuant
to the foregoing provisions, or otherwise, the Company has been advised that in
the opinion of the 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 Company of expenses incurred or paid by a director, officer or controlling
person of the Company in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the Company 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 1933 Act and
will be governed by the final adjudication of such issue.


                                       6
<PAGE>


                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS, that the undersigned officers and
directors of Avant! Corporation, a Delaware corporation, do hereby constitute
and appoint Gerald C. Hsu and Viraj Patel, each individually and without the
others, with full power of substitution and resubstitution, his true and lawful
attorneys-in-fact and agents, each with full power and authority to do any and
all acts and things and to execute any and all instruments which said attorneys
and agents, and either one of them, determine may be necessary or advisable or
required to enable said corporation to comply with the 1933 Act, as amended, and
any rules or regulations or requirements of the Securities and Exchange
Commission in connection with this Registration Statement. Without limiting the
generality of the foregoing power and authority, the powers granted include the
power and authority to sign the names of the undersigned officers and directors
in the capacities indicated below to any and all amendments, both pre-effective
and post-effective, and supplements to this Registration Statement, and to any
and all instruments or documents filed as part of or in conjunction with this
Registration Statement or amendments or supplements thereof, and each of the
undersigned hereby ratifies and confirms all that said attorneys and agents, or
either one of them, shall do or cause to be done by virtue hereof. This Power of
Attorney may be signed in several counterparts.

                                   SIGNATURES

         Pursuant to the requirements of the 1933 Act, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Fremont, State of California, on the 31st day of
August, 2000.

                                       AVANT! CORPORATION

                                       By /s/ GERALD C. HSU
                                         ----------------------------
                                         Gerald C. Hsu
                                         President and Chief Executive Officer


                                       7
<PAGE>



         Pursuant to the requirements of the 1933 Act, this Registration
Statement has been signed by the following persons, in the capacities
indicated on the 31st day of August, 2000.

<TABLE>
<CAPTION>

            SIGNATURE                                          TITLE

<S>                                   <C>

      /s/ GERALD C. HSU                   President, Chief Executive Officer and Chairman
  ------------------------------                       of the Board of Directors
      Gerald C. Hsu                                  (Principal Executive Officer)



      /s/ VIRAJ PATEL                                (Principal Financial Officer and
  ------------------------------                       Principal Accounting Officer)
      Viraj Patel

       /s/ MORIYUKI CHIMURA                                    Director
  ------------------------------
      Moriyuki Chimura

      /s/ CHARLES ST. CLAIR                                     Director
  ------------------------------
      Charles St. Clair

      /s/ KENNETH TAI                                           Director
  ------------------------------
      Kenneth Tai

      /s/ DANIEL D. TAYLOR                                      Director
  ------------------------------
      Daniel D. Taylor

</TABLE>

                                       8
<PAGE>


                                  EXHIBIT INDEX
<TABLE>

EXHIBIT NO.                                DESCRIPTION
-----------                                -----------
<S>                              <C>


     5                              Opinion of Farella Braun & Martel LLP

     23.1                           Consent of Independent Auditors

</TABLE>


                                       9