This paper reports that perovskite-type NiSnO3 semiconducting oxide can be used as a new type of gas sensitive material for detecting ethanol gas. NiSnO3 powders were prepared by a chemical coprecipitation synthesis method. The preparation conditions were carefully controlled. After calcination at 500 degreesC for 6 h, the n-type semiconductor gas-sensing material was obtained. The phase and microstructure of the powders obtained were characterized by X-ray diffraction. The product corresponds to perovskite-type NiSnO3, with a cubic habit over a small particle size range of 1-3 mum. The conductance-temperature, sensitivity-operating temperature and calcination temperature, sensitivity-gas concentration properties of NiSnO3-based sensors were investigated. It is found that sensors have good sensitivity to vapor of C2H5OH and good selectivity to petrol. Gas-sensing mechanism was studied with infrared and X-photo-electron energy spectra.