Ultra fine thin films of pure and SnO doped ZnO nanosensor were grown on gold digitated ceramic substrate from bis(2, 4-pentanedionate)dimethylethanolamine zinc (II) using bis(2, 4-pentanedionate) tin(II) chloride as a dopant by ultrasonic aerosol assisted chemical vapor deposition technique (UAACVD) at temperature range of 400-450 °C under oxygen atmosphere at 5 Pa pressure. The sensitivity, selectivity, fast recovery, and reliability test performed on nanosensor suggested that both doped and undoped ZnO thin films are suitable for detecting ethanol vapor in the temperature range of at 60 to 150 °C, whereas at room temperature (25 °C ) response and recovery time of the sensor increases many folds compared to 60 °C. Sensitivity of the ZnO sensor shows linear relationship with the increase of gas concentration. Electrical properties show that 1 % SnO doped ZnO enhanced the sensitivity of the film drastically and thus improved its detecting efficiency. Physico-chemical techniques like, CHNS-O, atomic absorption analyzer, and infra red and multinuclear nuclear magnetic resonance spectrometers were used for precursor characterization. X-ray diffractometer, scanning electron microscope, sigma scan analyzer and energy dispersive x-ray techniques were used for thin film characterization.