U.S. SECURITIES AND EXCHANGE COMMISSIONWashington, DC 20549

Form 40-F

oRegistration statement pursuant to section 12 of the Securities
Exchange Act of 1934

or

ýAnnual report pursuant to section 13(a) or 15(d) of the Securities Exchange Act
of 1934

|For the fiscal year ended December 31, 2003 |  | Commission File Number 0-25270
|------------------------------------------- |  | ------------------------------

Ballard Power Systems Inc.(Exact name of Registrant as specified in its charter)

CANADA(Province or other jurisdiction of incorporation or organization)

3261(Primary Standard Industrial Classification Code Number (if applicable)) Not applicable(I.R.S. Employer Identification Number (if applicable)) 4343 North Fraser Way
Burnaby, British Columbia V5J 5J9
(604) 454-0900

Corporation Trust Company
1633 Broadway
New York, New York 10019
(212) 894-8940Address (including zip code) and telephone number (including area code)
of agent for service in the United States)

Securities
registered or to be registered pursuant to Section 12(b) of the Act.

|Title of each class |  | Name of each exchange on which registered
|------------------- |  | -----------------------------------------
|Not applicable      |  | Not Applicable                           

Securities registered or to be registered pursuant to Section 12(g) of the Act. Common Shares

Securities
for which there is a reporting obligation pursuant to Section 15(d) of the Act.

Non-Applicable

For
annual reports, indicate by check mark the information filed with this Form:

|ý |  | Annual information form |  | o |  | Audited annual financial statements
|- |  | ----------------------- |  | - |  | -----------------------------------

Indicate
the number of outstanding shares of each of the issuer's classes of capital or common stock as of the close of the period covered by the annual report.

118,187,877 Common Shares

Indicate
by check mark whether the Registrant by filing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to
Rule 12g3-2(b) under the Securities Exchange Act of 1934 (the "Exchange Act"). If "Yes" is marked, indicate the filing number assigned to the Registrant in connection with such
Rule.

Yes

o

82-

No

ý


Indicate
by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act 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

ý

No

o




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Disclosure Controls and Procedures

As of the end of the period covered by this report, the Registrant's management (with the participation of its chief executive officer and chief financial
officer) conducted an evaluation pursuant to Rule 13a-15 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), of the effectiveness of the design
and operation of the Registrant's disclosure controls and procedures. Based on this evaluation, the Registrant's chief executive officer and chief financial officer concluded that as of the end of the
period covered by this report such disclosure controls and procedures were effective to provide reasonable assurance that information required to be disclosed by the Registrant in reports it files or
submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the rules and forms of the Securities and Exchange Commission.

Undertaking

The Registrant undertakes to make available, in person or by telephone, representatives to respond to inquiries made by the Commission staff, and to furnish
promptly, when requested to do so by the Commission staff, information relating to: the securities registered pursuant to Form 40-F; the securities in relation to which the
obligation to file an annual report on Form 40-F arises; or transactions in said securities.

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Signatures

Pursuant to the requirements of the Exchange Act, the Registrant certifies that it meets all of the requirements for filing on Form 40-F
and has duly caused this annual report to be signed on its behalf by the undersigned, thereto duly authorized.

|                   |  | Registrant:BALLARD POWER SYSTEMS INC.
|------------------ |  | -------------------------------------
|Date: May 18, 2004 |  |                                      
|                   |  | By (Signature and Title)             

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EXHIBIT LIST

|Exhibit |  | Description                                                                                                                                                                                                                   
|------- |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|99.1    |  | Annual Report for Ballard Power Systems Inc. for the year ended December 31, 2003, dated as of February 5, 2004 (incorporated by reference to the Form 6-K filed with the Securities and Exchange
Commission on May 17, 2004).
|99.2    |  | Annual Information Form for Ballard Power Systems Inc., dated as of March 31, 2004                                                                                                                                            
|99.3    |  | Certification pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                                                                       
|99.4    |  | Certification pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                                                                                                                                                       
|99.5    |  | Consent of KPMG LLP                                                                                                                                                                                                           
|99.6    |  | Comments by Auditor for U.S. Readers on Canada-U.S. Reporting Difference                                                                                                                                                      

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