The stability of drug product or a drug substance is a critical parameter which may affect purity, potency and safety. The stability indicating method is that employed for the analysis of stability samples in pharmaceutical industry. Forced degradation studies show the chemical behavior of the molecule which in turn helps in the development of formulation and package. Forced degradation is a degradation of new drug substance and drug product at conditions more severe than accelerated condition. Thus, this review discuss the current trends in performance of stability indicating method to force degradation by providing strategy for conducting studies on degradation mechanism Stability testing by reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been performed of cilinidipine and olmesartan. All the drugs were separated. The retention time of cilinidipine and olmesartan was founded respectively. Ranges of 50 -300μg/ml for cilinidipine and 25 – 150 μg/ml for Olmesartan. Keyword: Olmesartan, Cilnidipine, RP-HPLC.