a b s t r a c t Nanocrystalline cadmium oxide (CdO) thin films were deposited onto glass substrates by a chemical spray pyrolysis method using an aqueous solution of cadmium acetate. These films were characterized for their structural and morphological properties by means of X-ray diffraction (XRD), scanning elec-tron microscopy (SEM) and atomic force microscopy (AFM). The CdO films are oriented along (1 1 1) plane with the cubic crystal structure. These films were utilized in liquefied petroleum gas (LPG) sen-sors. The dependence of the LPG response on the operating temperature, LPG concentration and CdO film thickness was investigated. The CdO film showed selectivity for LPG over N 2 compared to CO 2