In the present work for the determination of Olmesartan Medoxomil, Hydrochlorothiazide and Amlodipine a simple, rapid and precise high performance liquid chromatography procedure has been developed and validated. The separation and quantification were achieved on a Cyano C18 column using a mobile phase of filtered and degassed mixture of buffer and acetonitrile in the ratio of 830:170 with of analytes at 237 nm. Buffer was prepared by dissolving 3.65 g of ammonium acetate in 1000 ml of water and the pH was adjusted to 7.0 with sodium hydroxide at flow rate of 1.5 ml/min. The method showed good linearity with different concentrations near to 0.99909, 0.99902 and 0.99871 for Olmesartan Medoxomil, Hydrochlorothiazide and Amlodipine respectively. The recovery (Average mean & RSD) were achieved as 102.18, 1.01 for Olmesartan Medoxomil, 102.58, 0.26 for Hydrochlorothiazide and 101.37, 0.26 for Amlodipine respectively. The precision (Average mean & RSD) were achieved as 99.9, 104.02 and 99.80 for Olmesartan Medoxomil, Hydrochlorothiazide and Amlodipine respectively.