A novel copper oxide (CuO)/polyethersulfone (PES) microporous ultrafiltration membrane was fabricated by the non-solvent induced phase inversion. A facile and single step method was used to synthesize CuO nanoparticles. The synthesized CuO nanoparticles were characterized by several methods like Fourier transform infrared spectroscopy, X-ray diffraction, distribution Light Scattering (DLS) and scanning electron microscopy (SEM) techniques. Any possible modification on the performance and morphology of the blended microporous membranes due to the different contents of CuO nanoparticle was investigated by SEM, energy dispersive X-ray (EDX), mean pore size, pore size distribution, water contact angle, atomic force microscopy (AFM) and permeation analyses as well as rejection and fouling tests. To investigate the kinetic of copper leaching from the blended membrane, copper release was measured. The asymmetric structure and the finger-like porous layer of the membranes were observed by SEM images. The morphology of the modified membranes did not significantly change by addition of CuO nanoparticles. The blended membranes with CuO had a reduction in water contact angle i.e. an enhancement in hydrophilicity and water flux due to insertion of hydroxyl groups of CuO nanoparticles on the surface of membrane. When the content of CuO nanoparticle was 0.2 wt%, the water flux achieved a maximum value (870 kg/m(2)h), while this value for unfilled PES membrane was 533 kg/m(2)h. Bovine serum albumin (BSA) solution filtration was the appropriate test for fouling resistance of the prepared membranes. The BSA filtration test showed that 0.1 wt% CuO/PES membrane had the best antifouling property.