Tin-doped cadmium oxide films were deposited by electron beam evaporation technique. The structural, optical and electrical properties of the films were characterized. The X-ray diffraction (XRD) study reveals that the films are polycrystalline in nature. As composition and structure change due to the dopant ratio and annealing temperature, the carrier concentration was varied around 1020 cm3, and the mobility increased from less than 10 to 45cm2 V1 s1. A transmittance value of 83% and a resistivity value of 4:4 104 cm were achieved for (CdO)0:88(SnO2)0:12 film annealed at 350 C for 15 min., whereas the maximum value of transmittance 93% and a resistivity value of 2:4 103 cm were obtained at 350 C for 30 min. The films exhibited direct band-to-band transitions, which corresponded to optical band gaps of 3.1–3.3 eV.