|EXHIBIT 31.2                                                                                                                                                                                                                                                                                                   
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|                                                                                                                                                                                                                                                                                                               
|CERTIFICATION                                                                                                                                                                                                                                                                                                  
|                                                                                                                                                                                                                                                                                                               
|I, Phil Marshall, certify that:                                                                                                                                                                                                                                                                                
|                                                                                                                                                                                                                                                                                                               
|1.   I have reviewed this report on Form 10-KSB of Capacitive Deionization Technology Systems, 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;
|                                                                                                                                                                                                                                                                                                               
|                                                                                                                                                                                                                                                                                                               
|                                                                                                                                                                                                                                                                                                               
|                                                                                                                                                                                                                                                                                                               
|                                                                                                                                                                                                                                                                                                               
|                                                                                                                                                                                                                                                                                                               
|Date: July 26, 2005                                                                                                                                                                                                                                                                                            
|                                                                                                                                                                                                                                                                                                               

| | /s/ Phil Marshall      
| | -----------------------
| | Phil Marshall          
| | Chief Financial Officer