The novel Ni/CdS composite photocatalyst was successfully synthesized by an efficient and simple photo-deposition method. Importantly, the morphology and structural characterization showed that the CdS prepared by solvothermal method was nanorod-like and no impurities. The deposited Ni nanoparticles are uniformly dispersed on the surface of the CdS nanorods. The optical properties results showed that it more conducive to absorption of light after introduction of Ni nanoparticles, which is beneficial to photocatalytic spite water to hydrogen evolution. The kinetic study indicants that the hydrogen production activity of the composite catalyst Ni/CdS (471.2 μmol) is about 70 times higher than that of the pure CdS (6.7 μmol) under the same conditions. In addition, the time of photo-deposition and the pH of the hydrogen production system have a great effect on the activity of the composite catalyst. The roles of Ni nanoparticles over CdS nanorods for improved photocatalytic stability and activity were systematically studied by means of SEM, TEM, XRD, XPS, UV–Vis absorption spectra and fluorescence spectra etc. The introduction of Ni nanoparticles has significantly enhanced the stability and activity of CdS nanorods. Ni nanoparticles act as electron outlet, it may combine with protons in the solution to form hydrogen molecules and can avoid the recombination of photogenerated electron hole pairs.