Combination of drugs is often formulated to increase the potency of the dosage form and to decrease the number of tablets taken for the management of diseases. In present work, methods of simultaneous estimation of Olmesartan Medoxomil and Amlodipine besylate in their combined dosage form are developed, as literature survey revealed that no method for simultaneous estimation of these drugs is reported. After studying the stability of both the drugs in methanol and acetonitrile, Olmesartan shows poor stability in methanol whereas in acetonitrile it shows good stability therefore acetonitrile is used for method development. Bioanalytical method validation was done by USFDA guidelines. Bioanalytical method validation was done by USFDA guidelines. Recoveries in all these method were in the range of 98-101%. Results obtained were statistically validated and were found to be reproducible. These methods can be applied for routine analysis of formulations containing these drugs. For analytical methods validation parameters such as linearity, precision, accuracy, specificity, limit of detection, limit of quantitation and robustness were determined according to ICH Q2B guidelines.