The polyacrylate emulsion coating modified by nano-silica was prepared by In-situ method. Tetraethoxysilane (TEOS) was added as the precursor of SiO2 in the late of the emulsion polymerization. The structure and properties of emulsion and latex film were characterized. The results showed that the nano-hybrid silica/polyacrylate emulsion coating with good performance can be prepared by In-situ method. FTIR analysis indicated that the -Si-O-Si- structure has embodied in the coating film. The particle diameter of emulsion is 378nm when nano-SiO2 content is 6% and the dispersing index is 0.164. The mechanical loss peak temperature (Tp) of coating film with 6% nano-SiO2 is 60.6°C which increase 6°C than pure emulsion film. The nano-hybrid emulsion coating has a good performance, such as good acid-alkali resistance and hardness.