Thin CdSe films were prepared under vacuum at different glass substrate temperatures. The effects of substrate heating and temperature on the X-ray diffraction patterns, electrical, DC current-voltage characteristics and photovoltaic properties were investigated in detail. the results obtained were interpreted mathematically, which led to a hopping conduction mechanism. Valuable semiconducting parameters were evaluated for the thin films investigated, for their useful application in photovoltaic or solar cell industries: surface charge density (4.8×1012 cm−2), thickness of depletion layer (7.4×10−7 cm) and donor concentration (6.5×1018cm−3).