Abstract: TiO₂/modified bentonite composite photocatalysts was prepared by ultrasonic-assisted sol-gel method with inorganic and organic modified bentonite. The micro-structure of materials were characterized by means of X-ray diffraction, IR spectroscopy respectively. The absorption and photocatalytic performance of composite photocatalysts were studied by using TNT as mode organic pollutants. The results showed that the interlayer spacing of inorganic modified bentonite decreases, while the interlayer spacing of organic modified bentonite increases. The modification can improve the absorption performance of bentonite and restrain the growing of the Ti; O₂ size, which can enhace the photocatalytic activities of TiO₂/bentonite composite photocatalysts.