PVP/EVAL blend membranes was prepared by blending of PVP with poly(ethylene-co-vinyl alcohol) (EVAL) via immersion precipitation and were used to separate the oil/water emulsion. The chemical structure, morphology, mechanical performance and hydrophilicity of PVP/EVAL blend membranes were characterized by FTIR-ATR, scanning electron microscopy, tension test and water contact angle measurement. The effect of PVP content on the separation performance of oil/water emulsion was investigated. The results indicate that PVP content had distinct effect on the morphology of PVP/EVAL membranes. The tensile strength and elongation at break of PVP/EVAL blend membrane with 10 wt% (the mass percent of PVP in the casting solution) PVP were 1.88 and 1.34 times, respectively, that of pure EVAL membrane. When the content of PVP increased to 4 wt%, oil/water emulsion flux of PVP/EVAL blend membrane were 1.81 times that of the pure EVAL membrane. The rejection ratio was 92.2 %, slightly higher than the pure EVAL membranes. When the content of PVP increased to 10 wt%, the flux recovery ratio after washing increased from 51 % to 77.98 %.