CA/TiO2 hybrid membranes were prepared via phase inversion by dispersing TiO2 nanopaticles in the CA casting solutions. TiO2 nanoparticles, which were synthesized by the sonochemical method, were added into the casting solution in different concentrations. The influence of TiO2 on the morphology and thermal stability of the CA/TiO2 membranes were investigated through the methods of scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). Permeation performance of the prepared membranes was evaluated in terms of pure water flux (PWF) and water content (WC). SEM results show that addition of TiO2 nanoparticles cause that the hybrid membrane becomes more porous because of increasing in the mean pore size. TGA results show that the interaction exists between the TiO2 nanopaticles and CA. Also the thermal stability of the hybrid membrane was improved by the addition of TiO2 nanopaticles. The membranes PWF shows that addition of TiO2 nanoparticles leads to the water permeation increase. (C) 2011 Elsevier B.V. All rights reserved.