---

SECTION 302 CERTIFICATION

I, William Murray, Chief Executive Officer, certify that:

|1. | I have reviewed this annual report on Form 20-F
        of PolyMet Mining Corp;                                                                                                                                                                                                                                                                         
|-- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  
|2. | Based on my knowledge, this annual 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 annual report;
|  
|3. | Based on my knowledge, the financial statements,
        and other financial information included in this annual report, fairly
        present in all material respects the financial condition, results of operations
        and cash flows of the registrant as of, and for, the periods presented
        in this annual report;                   
|  
|4. | The registrant's other certifying officers and I
        are responsible for establishing and maintaining disclosure controls and
        procedures (as defined in Exchange Act Rules 13a- 14 and 15d-14) for the
        registrant and have:                                                                                                         
|  

| | (a) | designed such disclosure controls and procedures
        to ensure that material information relating to the registrant, including
        its consolidated subsidiaries, is made known to us by others within those
        entities, particularly during the period in which this annual report is
        being prepared;
| | --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
| | (b) | evaluated the effectiveness of the registrant's
        disclosure controls and procedures as of a date within 90 days prior to
        the filing date of this annual report (the "Evaluation Date"); and                                                                                                                  
|
| | (c) | presented in this annual report our conclusions
        about the effectiveness of the disclosure controls and procedures based
        on our evaluation as of the Evaluation Date;                                                                                                                                        
|

|5. | The registrant's other certifying officers and I
        have disclosed, based on our most recent evaluation, to the registrant's
        auditors and the audit committee of registrant's board of directors (or
        persons performing the equivalent function):
|-- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|  

| | (a) | all significant deficiencies in the design or operation
        of internal controls which could adversely affect the registrant's ability
        to record, process, summarize and report financial data and have identified
        for the registrant's auditors any material weaknesses in internal controls;
        and
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
| | (b) | any fraud, whether or not material, that involves
        management or other employees who have a significant role in the registrant's
        internal controls; and                                                                                                                                                        
| |     |                                                                                                                                                                                                                                                                                                                               

|6. | The registrant's other certifying officers and I
        have indicated in this annual report whether or not there were significant
        changes in internal controls or in other factors that could significantly
        affect internal controls subsequent to the date of our most recent evaluation,
        including any corrective actions with regard to significant deficiencies
        and material weaknesses.
|-- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Date: July 22, 2005

| | /s/ William Murray                   
| | -------------------------------------
| | William Murray                       
| | President and Chief Executive Officer
| | (Principal Executive Officer)        

---