In this paper, the PAIUCPE was served as the working electrode, and used for the investigation of electrochemical behaviours and the reaction mechanisms of UA and FA. The anodic potential difference of UA and FA was about 324 mV and the simultaneous determination of UA and FA was achieved based on it. Moreover, the PAIUCPE exhibited low cost, reliable performance, long service life and non-pollution on environment. The proposed method was of high sensitivity as well as a wide linear region that made it used for the simultaneous determination of UA and FA in human urine with satisfactory results.