Cd1-xZnxO thin films were prepared by spray pyrolysis in air atmosphere on a glass substrate at 250 degrees C. The Zn content in Cd1-xZnxO films was varied from x = 0 to 0.60. Structural, electrical and optical properties of Cd1-xZnxO films were investigated by x-ray diffraction, electrical resistivity and optical transmittance spectra, respectively. As the Zn content in Cdl-xZnxO thin films increased, the preferred orientation of the films did not change, only the peak intensity of the planes decreased. In addition to the peaks of CdO, peaks of ZnO were observed in the film with x = 0.6. The resistivity of Cd1-xZnxO thin films increased with increasing Zn content. Transmittance spectra studies of films were carried out in the 190-1100 nm wavelength range and the results showed that the bandgap energy range varied from 2.42 to 3.25 eV. In addition, alloying effect on the K beta/K alpha intensity ratio in Cd1-xZnxO semiconductor thin films was studied. It was found that the K beta/K alpha intensity ratio is changed by alloying effects in Cd1-xZnxO semiconductor thin films for different composition of x. The results were compared with the theoretical values. Copyright (c) 2006 John Wiley & Sons, Ltd.