Nanosize CdS semiconductor particles were synthesized using the solvothermal technique. The structure was characterized by means of XRD,TEM and ED techniques. PANI film was prepared by electro-chemistry method onto the indium-tin oxide glass. The nanoparticles were doped on PANI film by the dipping process, and the self-assembled nanoparticles-PANI composite film was acquired. The photoelectric properties of the self-assembled film were studied by PL and Z-scan method.