Abstract: A sensitive high-performance liquid chromatographic (HPLC) method were developed and validated for the estimation of Diclofenac sodium and Pantoprazole in bulk and pharmaceutical formulations. The chromatographic separation was achieved by RP- HPLC using a mixture of methanol: Phosphate buffer (10mM) in ratio 80:20 pH 3.5 as the mobile phase with isocratically system, a C18 column & the eluents was monitored using UV detector at 284 nm. The pH is adjested by ortho phosphoric acid.