In this study, we investigated the ability of TiO2 self-assembled nanocomposite membranes to mitigate fouling effects during the filtration of membrane bioreactor (MBR) mixed liquor. Our results showed that membrane fouling was significantly reduced by the immobilization of TiO2 nanoparticles on the surface of these membranes. The fouling mitigation effect increased with increasing amounts of TiO2 nanoparticles and the initial sharp flux decline observed for neat polymeric membranes was alleviated by TiO2 immobilization. Adsorbed foulants on the surface of nanocomposite membranes were more readily dislodged by shear force than those on neat polymeric membranes due to the increased hydrophilicity of the membrane. Accordingly, the amount and the rate of membrane fouling decreased in the nanocomposite membranes. (c) 2005 Elsevier B.V. All rights reserved.