Poly(perfluoroalkyl acrylate)(PFA) /silica composites having different silica size were prepared by surface polymerization. In this study, surface characterizations of PFA/silica composites were done by HR-TEM(High Resolution Transmission Microscopy), contact angle measurement, sliding angle measurement, surface roughness measurement, and the relationships between the sliding angle and the contact angle were investigated. In the highly hydrophobic region, the sliding angles of water droplets decreased with increasing contact angle. Their surface free energies were calculated with contact angle data by geometric mean approximation. The composites with super water repellent and sliding could be obtained with contact angle of above 150 ° and sliding angle of below 10 ° to water droplets. The ultimate value of surface free energies of the composites reaches below ca. 1 dyn/cm.