A simple, specific and LC-MS compatible reverse phase liquid chromatographic method was developed for the simultaneous estimation of Hydrochlorothiazide (HCT), Amlodipine Besylate (AML) and Olmesartan Medoxomil (OLM) in bulk and pharmaceutical dosage forms. A C18 reverse phase column (Develosil- RP Aqueous) of 250 x 4.6mm dimensions and 5μm particle size with mobile phase containing 0.1%v/v formic acid: acetonitrile (60:40% v/v) was used at isocratic mode and eluents were monitored at 254nm. The retention times of HCT, AML and OLM were 3.91, 5.50, and 7.62min respectively and showed a good linearity in the concentration range of 5-25μg/mL with a correlation coefficient (R) of 0.9998, 0.9996 and 0.9994 respectively. The percentage assays were found to be 99.20, 97.20, and 98.90 respectively for HCT, AML and OLM. The proposed method was validated as per ICH guidelines and successfully applied to the simultaneous estimation of HCT, AML, and OLM in tablet formulations.