Abstract: Novel organic-inorganic hybrid membranes were prepared through sol-gel reaction of poly（vinyl alcohol）（PVA）with γ-aminopropyl-triethoxysilane（APTEOS）.The resulting membranes were characterized with Fourier transform infrared spectroscopy and wide-angle X-ray diffraction.The swelling degree of PVA and PVA/APTEOS hybrid membranes in water/ethanol mixture was determined.The pervaporation performance was investigated by separation of water/ethanol mixture at 50℃.The effect of APTEOS content on the pervaporation performance was studied.The decrease in swelling degree with increasing APTEOS content was due to the formation of hydrogen and covalent bonds in the membrane matrix.The crystalline region of PVA decreased with increasing APTEOS content.The separation factor for water increased，and then decreased when APTEOS content was more than 5.0%(mass).The hybrid membrane containing 5.0%(mass) APTEOS exhibited the highest separation factor.However the permeation rate increased remarkably with increasing APTEOS content.The trade-off relation of the PVA membrane was solved，and the PVA/APTEOS hybrid membranes showed high pervaporation properties.