A series of polyethersulfone (PES) - multi-walled carbon nanotube (MWCNT) (C/P) composite membranes with different amounts of MWCNT were prepared using the phase inversion process. The influence of addition of MWCNT on the morphologies, permeation properties and the antifouling performances of C/P composite membranes were investigated through the methods of scanning electron microscopy (SEM), contact angle goniometer, pure water flux test and permeation tests. The results showed that addition of MWCNTs significantly increased the hydrophilicity, pure water flux and solute rejection of the membranes. Antifouling tests showed that the C/P composite membranes have a stronger ability to resist fouling than that of bare PES membrane. The membrane with 2 wt% MWCNT addition displayed ideal permeation properties in pure water flux, solute rejection and antifouling ability. © 2011 American Chemical Society.