Abstract: Oscillopolarography was applied to the determination of microamounts of pioglitazone hydrochloride in drugs.In an ammonicacal buffer of pH 8.8,a sensitive polarographic reductive wave given by pioglitazone was observed at -1.42 V (vs.SCE).Linear relationship between the values of 2st derivative of peak current (I″p) and concentration of pioglitazone was obtained in the range of 0.4-40 mg·L-1.Conditions for the method of determination were studied and optimized.The electrochemical behavior of pioglitazone at the dropping mercury electrode and mechanism of the electrode reaction were also studied.The proposed method was used in the analysis of a drug for its pioglitazone content,giving results in consistency with the labelled value and also checked with results found by HPLC.Value of RSD (n=10) found was 3.04%.