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                                                                    EXHIBIT 12.1

              CERTIFICATION OF CHIEF EXECUTIVE OFFICER REQUIRED BY
   RULE 13A-14(A) OR RULE 15D-14(A) UNDER THE SECURITIES EXCHANGE ACT OF 1934

I, Richard Lau, certify that:

         1. I have reviewed this annual report on Form 20-F of Deswell
Industries, Inc.

         2. Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

         3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the company as of,
and for, the periods presented in this report;

         4. The company's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the company and have:

                  (a) Designed such disclosure controls and procedures, or
         caused such disclosure controls and procedures to be designed under our
         supervision, to ensure that material information relating to the
         company, including its consolidated subsidiaries, is made known to us
         by others within those entities, particularly during the period in
         which this report is being prepared;

                  (b) Evaluated the effectiveness of the company's disclosure
         controls and procedures and presented in this report our conclusions
         about the effectiveness of the disclosure controls and procedures, as
         of the end of the period covered by this report based on such
         evaluation; and

                  (c) Disclosed in this report any change in the company's
         internal control over financial reporting that occurred during the
         period covered by the annual report that has materially affected, or is
         reasonably likely to materially affect, the company's internal control
         over financial reporting; and

         5. The company's other certifying officer(s) and I have disclosed,
based on our most recent evaluation of internal control over financial
reporting, to the company's auditors and the audit committee of the company's
board of directors (or persons performing the equivalent functions):

                  (a) All significant deficiencies and material weaknesses in
         the design or operation of internal control over financial reporting
         which are reasonably likely to adversely affect the company's ability
         to record, process, summarize and report financial information; and

                  (b) Any fraud, whether or not material, that involves
         management or other employees who have a significant role in the
         company's internal control over financial reporting.

Date: July 16, 2004
                                                    /s/ Richard Lau
                                                    ----------------------------
                                                    Richard Lau
                                                    Chief Executive Officer