A simple, rapid, economical, precise and accurate Stability indicating RP-HPLC method for Acotiamide HCl Hydrate In its Pharmaceutical Dosage Form has been developed. A reverse phase high performance liquid chromatographic method was developed for the Acotiamide HCl Hydrate in its Pharmaceutical Dosage Form has been developed. The separation was achieved by Hypersil BDS C18 (25 cm × 0.46 cm) 5μ, column and Water (pH 4.5): Methanol: TEA (45:55:0.1) as mobile phase, at a flow rate of 1 ml/min. Detection was carried out at 222 nm. Retention time of Acotiamide HCl Hydrate was found to be 4.420 min. The method has been validated for linearity, accuracy and precision. Linearity observed for Acotiamide HCl Hydrate 5-15 μg/ml. Developed method was found to be accurate, precise and rapid for simultaneous estimation of Acotiamide HCl Hydrate in its Combined Dosage Form. The drug was subjected to stress condition of hydrolysis, oxidation, photolysis and Thermal degradation, Considerable Degradation was found in Thermal degradation. The proposed method was successfully applied for the estimation of its dosage form. Keywords: Acotiamide HCl Hydrate, Stability indicating RP-HPLC Method, Validation.