A simple, rapid and sensitive RP-HPLC method for the quantification of pioglitazone hydrochloride in bulk drug and tablet formulation was developed and validated. Chlordiazepoxide was used as internal standard. The separation was achieved on a Nucleodur 100-5 C18 column (250 mm× 4.6 mm i.d., 5 m particle size). The mobile phase consisted of methanol-0.07 M formic acid (57:43, v/v) at a flow rate of 0.9 mL/min and detection was performed at 266 nm using photodiode array (PDA) detector. The drug was subjected to various ICH prescribed stress conditions including hydrolysis (acid and alkaline), oxidation, photolysis and thermal degradation. Degradation in acid, base and peroxide was found in range 36-45%. The proposed method was validated with respect to specificity, linearity, accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), stability, and robustness as per ICH guideline. The developed method was found to be successively applied for the quality control of pioglitazone hydrochloride in bulk drug and tablets as well as the stability indicating studies.