In this work, a tungsten trioxide (WO3) based sensitive gas sensor is developed and described. The WO3 material is synthesized using sol-gel method and deposited over fabricated interdigitated electrodes (IDE) by drop casting method. The morphology, surface composition and structural properties of the deposited WO3 film were investigated. The XRD and SAED show the monoclinic structure of WO3. The sensor shows highly selective nature towards nitrogen dioxide (NO2) in the presence of different interfering gases like SO2, NH3, Cl-2, CH3OH and C3H6O. The NO2 gas responses for the 5-100 ppm concentrations were Investigated at an optimum operating temperature of 200 degrees C. The sensor has an excellent reproducible gas response and supreme stability.