Abstract:A method to deposit hematite (Fe2O3) thin films by plasma-enhanced chemical vapor deposition (PECVD) is introduced. The structure and particle-size of Fe2O5 thin film are analysed by X-ray diffraction and SEM, respectively. The gas sensitive properties of thin film to LPG, coal gas, hydrogen and ethanol are studied. The results show that films prepared in this way are highly sensitive to ethanol. However, it is not so sensitive to LPG, coal gas or hydrogen. Therefore the film is proved to have high selectivity.