A gradient reverse-phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for the determination of Prasugrel hydrochloride and its related substances. The well chromatographic separation of prasugrel from its seven related substances and degradation products was achieved on Sunfire C18, 5m (250mm x 4.6mm) column temperature maintained at 45°C with a mobile phase A: 0.1% v/v orthophosphoric acid in water and mobile phase B: 0.1% v/v orthophosphoric acid in acetonitrile. The flow rate was 1.0mL/min, and the detection wavelength was 220nm. The developed method was validated for specificity, forced degradation studies, sensitivity (LOD and LOQ), linearity, precision (system precision, method precision and intermediate precision), accuracy, stability of standard and sample solutions and robustness. The method is linear with a concentration range of 0.085-3.218µg/ml with correlation coefficients more than 0.9997 for prasugrel and its related substances. The method recoveries obtained are ranged between 96.4% -101.1% for LOQ levels and 94.7%-103.3% for remaining levels. The method was found to be specific, linear, sensitive, precise, rugged, accurate, robust and stability indicating in nature. The more results are detailed in research paper.