Ni-W-P base composites containing CeO 2 and SiO 2 nano-particles were prepared on common carbon steel surface by pulse co-deposition of Ni, W, P, CeO 2 and SiO 2 nano-particles. The influence of SiO 2 concentrations in bath on microstructures and properties of Ni-W-P/CeO 2 -SiO 2 composites was studied, and the characteristics were assessed by chemical compositions, element distribution, surface morphologies, deposition rate and microhardness. The results indicate that when SiO 2 concentration in bath is controlled at 20 g/L, the composites possess the fastest deposition rate, the highest microhardness, compact microstructures, smaller crystallite sizes and uniform distribution of W, P, Ce and Si within Ni-W-P matrix metal. Increasing SiO 2 concentration in bath from 10 to 20 g/L leads to the refinement in grain size and the inhomogeneity of microstructures. While when SiO 2 concentration is increased to 30 g/L, the crystallite sizes increase again and some bosses with nodulation shape appear on the surface of composites.