A simple, precise, rapid ,reproducible, accurate and stability indicating RP-HPLC method has been developed for the determination of new antipsychotic agent paliperidone in pharmaceutical formulation. zorbax –SB-phenyl, 150x4.6mm; 3.5Im particle size column was used with variable wavelength UV detector. The mobile phase consisting of PH 4 Buffer and Acetonitrile 80:20 v/v was used. The flow rate was 1 ml/min and the effluent was monitored at 238 nm. The retention time of drug was 0.9. The method was linear over the concentration range of 1.0 mg/ml. The method precision for the determination of assay was below 2%RSD. The percentage recovery of paliperidone was 85-115%. The validation of method was carried out utilizing ICH Q2 (R1) guidelines.