Nano-CdS/PAOAA composite film was prepared on matrix of PAOAA which was synthesized by copolymerization of aniline with o-anthraniline. The size of CdS nanoparticles is uniform and its size distribution is narrow, these particles can exist in matrix stably. The size of CdS particles increased with the increase of sulfuration time. The PL spectrum of nano-CdS/PAOAA composite film indicated that, PL emission originated from PAOAA and CdS nanoparticles together, whose peaks emerge around 430nm and 520nm. Growing of CLIS particles resulted to more electron-hole pairs composited in CdS. It indicates that the characteristic peak of CdS get stronger in PL spectra of nano-CdS/PAOAA composite film, white the characteristic peak of PAOAA gel weaker.