Exhibit 99.5

CFO SECTION302CERTIFICATION

I, Claude Mongeau, certify that:

| | (1) | I have reviewed this annual report on Form 40-F of Canadian National Railway Company;                                                                                                                                                                                                                     
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| | (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;
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| | (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 issuer as of, and for, the periods presented in this report;                       
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| | (4) | The issuer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 issuer and have:                                                                                       
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| | (5) | The issuer's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the issuer's auditors and the audit committee of
the issuer's board of directors (or persons performing the equivalent functions):
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| |     | (b)                                                                                                                                                                                                                                                                                
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Date: March 21, 2006

| | /s/ Claude Mongeau                                  
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| | Claude Mongeau                                      
| | Executive Vice-President and Chief Financial Officer

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