Two novel cardo poly(arylene ether sulfone)s, one bearing pendant zwitterionic carboxybetaine groups (PES-CB) and the other bearing pendant sulfobetaine groups (PES-SB) were synthesized and used for preparation of asymmetric membranes by the phase inversion method. The chemical structure, thermal, and mechanical properties of the membrane materials were thoroughly characterized. The antifouling effect of the resultant membranes were measured both under static and dynamic protein adsorption experiments. The carboxybetaine poly(arylene ether sulfone) (PES-CB) membrane performed significant resistance to protein adsorption. After three cycles of lysozyme solution filtration, a water flux recovery ratio as high as 95% was achieved for the PES-CB ultrafiltration membrane, whereas only about 25% of water flux recovery ratio was obtained for the conventional poly(arylene ether sulfone) cardo (PES-C) ultrafiltration membrane. (C) 2009 Elsevier B.V. All rights reserved.