Polyvinylidene fluoride (PVDF) membranes were used to regenerate used rolling oil (URO). The effects of PVDF content, solvent and pore-forming agent (PFA) on the membrane structure were investigated. The physical properties of recycled oils filtered with different PVDF membranes were also evaluated experimentally. When the PVDF content increased to 18% in the N, N-dimethylformamide (DMF) and polyvinyl pyrrolidone (K15) treated PVDF membrane, the pore size was the smallest and the mesopores were evenly distributed on the membrane surface. Numerous large-particle impurities, including gum, asphaltene, metal particles, heavy aromatic hydrocarbons and isoparaffins, were entrapped.