In the present work a simple, inexpensive, rapid, easy, sensible and reproducible UV Spectrophotometric method has been developed and validated for determination of Olmesartan (OLM) and Hydrochlorothiazide (HCT) in bulk drug and pharmaceutical dosage form. A simple double beam UV spectrophotometric method has been developed using area under curve method and validated with different parameters such as linearity, precision, Accuracy, limit of detection (LOD), Limit of Quantification (LOQ), accuracy as per ICH guidelines. UV-visible spectrophotometric method, measurement of absorption at maximum wavelength in 10 ml methanol and volume make with water solvent system as reference OLM and HCT were found to be at 256 nm and 276 nm respectively. The drug obeyed the Beer’s law and showed good correlation. Beer’s law was obeyed in concentration range 2-32 µg/ml for Olmesartan and Hydrochlorothiazide respectively with correlation coefficient was 0.999. LOD values for OLM and HCT were found to be 0.056 µg/mL and 0.1050 µg/mL respectively and LOQ values for OLM and HCT were found 0.1698 µg/mL and 0.3183 µg/mL respectively. The proposed method is precise, accurate and reproducible and can be used for routine analysis of OLM and HCT in bulk and pharmaceutical dosage form.