Fluorine-containing polyacrylate composite emulsion modified by active nano TiO2 was prepared with -methyl methacrylate alkoxy silane (KH570), nano - TiO2 modified by KH570, perfluorinated octyl ethyl acrylate (FM) as the main raw material, and copolymerized with propenyl monomers. The structure and performance of copolymer were studied by means of infrared spectroscopy (FT-IR), atomic force microscope (AFM) and contact angle measuring instrument. The results showed that the modified nano-TiO2 and fluorinated monomers were successfully introduced into polyacrylate copolymer. The granules were spherical, smooth and monodisperse with an average of 184nm. Compared with acrylate polymer, the roughness of modified film was improved, which was advantageous to the waterproof and oilproof. The addition of fluorine and silicon monomer largely increased the contact angle, and the contact angle of water and diiodomethane was 125° and 110° respectively. At last, the composite emulsion was used as a paper surface sizing agent, the water contact angle was 147°, the diiodomethane contact angle was 133°, the paper’s waterproof and oil repellency were significantly increased with the introduction of fluorine monomer.