TiO2 coated with CdS (CdS/TiO2) composite nanoparticles were prepared by chemical precipitation method. They were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and UV-vis diffuse reflection absorption spectra. The activity of sample was explored with photocatalytic hydrogen evolution under visible light irradiation as a probe reaction. The results showed that the particle size of composite nanoparticles was about 40nm. TiO2 and CdS in the composites could be indexed to an anatase phase and hexagonal crystal, respectively. The absorption edge of composites showed an obvious red-shift and absorption peak was appeared in the visible light region. The experimental of photocatalytic hydrogen generation showed that the composites had high activity of hydrogen generation and stability.