A RPHPLC chromatographic method was developed and validated for the determination of Quinapril and Hydrochlorothiazide in bulk powder and in pharmaceutical formulations. Quinapril and Hydrochlorothiazide can be separated on Zorbax Eclipse XDB, C18 column (150 x 4.6 mm, 5 mm) at 30 C using Acetonitrile: Phosphate buffer, pH 4.5 was adjusted with o-phosphoric acid in the ratio of 35:65 v/v as a mobile phase at flow rate of 0.9 mL min-1 and detected at 210 nm. The retention time of Quinapril and Hydrochlorthiazide was found to be 2.099 min and 5.537 min respectively. The validation of the proposed method was carried out for specificity, linearity, accuracy, precision, LOD, LOQ and robustness. Calibration was linear over a range of 50-300 g mL-1 and 31.25187.5 g mL-1 with correlation coefficient of 0.999 for Quinapril and Hydrochlorthiazide, respectively. The robustness of the method was evaluated by deliberately altering the chromatographic conditions. The method developed can be applicable for quality control analysis.