A simple and effective RP-HPLC method had been developed for the estimation of vorinostat in capsule, using Apollo C18 (4.6 x 150mm, 5mm), mobile phase 100% methanol, detection wavelength at 247 nm, at flow rate of 1ml/min at retention time 3.43 min for vorinostat. Linearity was obtained in the range of 5µg/ml to 25µg/ml for vorinostat. The correlation coefficient was found to be 0.999. The Recovery studies were performed for vorinostat in the range of 50% - 150 %. The % Assay for vorinostat is 99.85 % .Forced Degradation studies were conducted according to the ICH guidelines and the Drug Product was found to be stable in all conditions. Hence, the method could be successfully applied for routine analysis of vorinostat capsules.