The study describes development of a stability indicating RP - HPLC - PDA method for the estimation of Oxcarbazepine in bulk form with the mobile phase compatible to LC-MS analysis. The proposed method utilizes a Phenomenex C18 column (150 mm x 4.6 mm, 5.0 μ particle size), at ambient temperature, optimum mobile phase consisted of methanol: formic acid (0.02%) in the ratio of 50:50 (v/v). The flow rate was optimized to 1mL/min and the detection was carried at 229 nm. The drug substance was exposed to hydrolytic, oxidative, thermal and photolytic stress conditions, and the resultant samples were analysed by the proposed method.