Ag doped ZnO films (ZnO：Ag) were deposited on quartz glass substrates by ultrasonic spray pyrolysis technology. Zn(CH3COO)2 and Ag(NO3)3 aqueous solution were used as the sources of Zn and Ag， respectively. The effect of substrate temperature on structural， electrical and optical properties of ZnO：Ag films were studied using X-ray diffraction， Hall effect measurement， photoluminescence spectra， and transmittance spectra measurement. All the measurements were performed at room temperature. It is found that the electrical and optical properties of the obtained ZnO：Ag thin films change dramatically due to Ag doping. The Ag doped p-type ZnO films with hole carrier concentration of 5.295×1015cm-3 and Hall mobility of 6.61cm2·V-1s-1 at room temperature have been successfully obtained at optimal conditions. In photoluminescence measurements， a strong ultraviolet emission centered at 379nm and a relatively weak green emission band were observed， and in transmittance measurements， a high transmittance of～70% in the visible region and a sharp absorption edge at 375nm were observed for all samples.