Abstract: Anatase TiO₂ films were prepared by micro-arc oxidation, and CdS particles were deposited onto the prepared TiO₂ films by chemical bath deposition (CBD) with various deposition times. X-ray diffraction showed that the phase of TiO₂prepared by micro-arc oxidation was anatase, and CdS prepared by CBD method was grown dominantly by the ion-by-ion process on the TiO₂ films. The resultsof scanning electron microscopy (SEM) and photocatalytic degradation of methylene blue under visible light indicated that the best CdS/TiO₂ couple with fine CdS particles dispersed equally on TiO₂ film was obtained after 15 min deposition ofCdS, and the diameter of the vast majority particles was nano scale. The coupled semiconductor had good catalytic activity in decomposition of methylene blue. As compared with TiO₂, the photocatalytic activity of the couple increased significantly under visible light illumination. Combined with the results of the photocatalytic evaluation, the photosensitization mechanism of the coupled semiconductorwas also discussed.