**Exhibit      99.5**

**CERTIFICATION          PURSUANT TO RULE 13a-14 OR 15d-14 OF THE **
**SECURITIES          **

**EXCHANGE          ACT OF 1934, AS ADOPTED PURSUANT TO **
**SECTION          302 OF THE **

**SARBANES-OXLEY          ACT OF 2002**

| 1. | I                    have reviewed this annual report on Form 40-F of YM BioSciences                    Inc.; |
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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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|   | (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 issuer, 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; |
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|   | (b) | Evaluated                    the effectiveness of the issuer’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 |
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|   | (c) | Disclosed                    in this report any change in the issuer’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 issuer’s internal control over financial reporting;                    and |
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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                    function): |
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|   | (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 issuer’s ability to record,                    process, summarize and report financial information;                    and |
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|   | (b) | Any                    fraud, whether or not material, that involves management or other                    employees who have a significant role in the issuer’s internal control                    over financial reporting. |
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| Dated: September                    21, 2006 |                                                                                                           |                                  |
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|                                              |                                                                                                           | /s/                    Leonard Vernon |
|                                              | Leonard Vernon                                                                                            |
|                                              | Vice                    President, Finance and Administration (Principal Financial                    Officer) |