This paper studied Sol-gel synthesis of PES/TiO2 hybrid membrane, the process utilizes TEM transmitting the casting solution to characterize the degree of dispersion, and characterizes the morphologies of membrane surface and cross – section by SEM, testing the hydrophily by contact angle measurement instrument. The results show that, when the adding amount of TiO2  gel are 4%, there are amounts of TiO2 nanoparticles distributing evenly on the surface, and only exist fingerlike pores , the thickness of skin layer increasing, inferior layer disappeared. The composite membranes held excellent water permeability, this improved the hydrophily of the membranes and the resistance of pollution. With the increasing of the concentration of TiO2 nanoparticles, the TiO2 nanoparticles cannot distribute evenly because of the aggregate of nanoparticles. When the membranes suffer from external force, the interior will cause local stress concentration and the mechanical property declined.