Abstract: TiO_2 nanoparticles were loaded on the Fe-MCM-41 mesoporous molecular sieves after the surface chemical modification of Fe-MCM-41 with KH-550 under different conditions. It was found that the polarities of the solvents in the silylanization have great influences on the adsorbability of photocatalyst composite. X-ray diffraction (XRD), diffuse reflectance ultra-violte-visible spectrum (UV-Vis), Fourier transform infrared spectrum (FT-IR) and N_2 adsorption/desorption isotherms were used to characterize the TiO_2-Fe-MCM-41 composite. It was shown that Fe-MCM-41 has different silylanization extent with KH-550 in the different solvents. Comparing with those modified in polar solvents, the composite modified in hexane has much stronger adsorbability and better dispersive ability to TiO_2 nanoparticles.