Thin films of Zn100-xCdxO with x = 0, 2, 4, 6 and 8 at% were deposited by electron beam evaporation technique on glass substrates. The structural, optical and electrical properties of Zn100-xCdxO films with x = 4 at% have been investigated as a function of annealing temperature. Only zinc and cadmium appeared in the as-deposited films, by annealing their oxides found to exist. It was observed that the optical properties, such as transmittance, reflectance, optical band gap, and refractive index of Zn100-xCdx, were strongly affected by annealing temperature. Other parameters named free carrier concentration, electrical resistivity of the films were studied as a function of annealing temperature for 4 at% CdO content. The figure indicates that the best value of annealing temperature is at 450℃.