SnO2 and SnO2/Zn, at the Zn percentages of 10 and 30, films were prepared at the substrate temperature of 350 +/- 5degreesC by ultrasonic spray pyrolysis (USP) technique, and the effect of Zn incorporation on the some physical properties of SnO2 films was investigated. To possess information about the electrical properties of all films, their electrical resistivities, conduction mechanisms, activation and trap energies were investigated. The film structures were studied by X-ray diffraction. Surface morphologies and elemental analyses of the films were studied scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. It can be inferred from all investigations that some physical properties of SnO2 films remarkable changed with Zn concentration. (C) 2004 Elsevier B.V. All rights reserved.