Polyacrylate/nano-SiO2 was prepared by Pickering emulsion polymerization using modified nano-SiO2 powders as stabilizer of acrylic monomers. Taking monomer conversion rate and gel rate as examining index, the most optimization condition of the emulsion polymerization was established by the experiments. Morphology of Pickering emulsion was observed by optical microscope. The polyacrylate/nano-SiO2 latex and film was characterized by Dynamic Light Scattering (DLS), Transmission Electron Microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope（SEM）. The results indicated that the emulsion was best when the mass ratio of SiO2 to triethoxyvinylsilane (A-151) at 5 to 1 and the mass ratio of MMA to BA at 1 to 4. FTIR result showed that the nano-SiO2 was successfully introduced. The results of DLS and TEM indicated that the latex particles had uniform size, and the size was roughly 790nm. SEM result showed that the nano-SiO2 was dispersed into the composite latex film. The polyacrylate/nano-SiO2 emulsion was applied in leather finishing process. The results show that compared with polyacrylate emulsion coating leather sample, permeability, water vapor permeability and dry wet rub resistance of leather samples coated by polyacrylate/nano-SiO2 composite emulsion were improved.