Abstract: TiO₂/MCM-41 photocatalysts with different titania content were prepared by loading titania onto the mesopores of MCM-41 molecular sieves via a sol- gel method. The photocatalytic activities of TiO₂/MCM-41 photocatalysts were evaluated by the photocatalytic degradation of Rhodamine B aqueous solution.TiO₂/MCM-41 photocatalysts were characterized by X-ray diffraction （XRD）,UV- Vis diffuse reflectance spectroscopy and N₂ adsorption techniques. The results indicate that both the BET surface area and pore volume of TiO₂/MCM-41 photocatalyst decrease with the increase in content of loaded titania. The average crystal size of titania loaded on TiO₂/MCM-41 is smaller than that of pure titania nanoparticles. 20% TiO₂/MCM-41 photocatalyst has the highest photo- induced charge separation efficiency. Among all the photocatalysts,the 20% TiO₂/MCM-41 sample possesses the best photocatalytic activity. The h⁺ is main active species during the photocatalytic process. The photocatalytic activities of the TiO₂/MCM-41 photocatalyst depend on their adsorption abilities and the activity of titania loaded onto the MCM-41 molecular sieves.