Recently, the fabrication of porous materials with micro/nano rough structures based on the models of special wettability have attracted considerable attention in the field of oil-water separation. In order to satisfy demands of highly efficient and high flux gravity directed oil-water emulsions separation in different situations, in this study, a series of polypropylene (PP) fabrics with different super wettability and roughness are fabricated by modifying the PP fabrics with different amounts of SiO2 nanoparticles. The performances of W/O and O/W emulsions separated by PP fabrics with different pore size and surface energy were experimentally observed, and the results showed that, the modified fabrics exhibited excellent water/n-hexane and water/toluene emulsion separation performance with separation efficiencies > 99.5% and fluxs > 700 L/(m2·h). Furthermore, the corresponding separation mechanisms were investigated, which provide a theoretical basis for the scientific design and controllable fabrication of future oil-water emulsion separation materials.