Chromatographic separation was achieved on Purospher STAR RP-18e 250 mm long, 4.6 mm inner diameter and 3μm particle size column. Perchloric acid buffer and acetonitrile was used as mobile phase at the flow rate of 1.0 ml/min with gradient composition. Injection volume was set as 20 μl and UV detection was made at 238 nm. Proposed method was validated as per ICH Q2A guidelines. Inter and intra-day precision of the method was studied and found the method is repeatable and reproducible. Solution stability was carried out up to 24 h. Proposed method LOD was <0.007% and LOQ was <0.012%. Linear response were observed against the respective concentration and regression coefficient of the linear curve r2 was >0.999. Accuracy was studied in four different concentrations in triplicate (LOQ,50, 100&150% with respect to sample concentration).Accuracy of LOQ level was observed between 91 and 112% of recovery, and the other level recovery was between 93 and 105%. Five common impurities of Paliperidone and Risperidone was separated and validation was demonstrated.