CdS and Se thin films were deposited on slide glass by EBE method respectively and surface morphology, crystal structure, electrical and optical properties were investigated by substrate temperature and annealing. The deposited CdS film was well fabricated with cubic structure at substrate temperature of $150^{circ}C$. Se film was deposited with noncrystal structure until substrate temperature of $100^{circ}C$, but Se film was grown with monoclinic structure at substrate temperature of $150^{circ}C$. And so, after annealing at $150^{circ}C$ for 15min, noncrystalline Se was proved to be hexagonal structure. Finally, the maximum output of Se/CdS heterojunction at 5000 lux was 4 $mW/cm^{2}$ and maximum spectral sensitivity was represented at 585nm.