Abstract: Nano-SiO2 was used as the matrix synthesised by Stöber method. The phenolic resin and hexadecyl trimethyl ammonium bromide (CTAB) was introduced to prepared SiO2/TiO2 mesoporous composite microspheres. Then the crystal structure, morphology , structure of the materials had been characterized by XRD, SEM, EDS , BET, BJH and FI-IR. Rhodamine B, the target degradation products, was used to evaluate the photocatalytic performance of the samples.The characterization results showed that the SiO2/TiO2 mesoporous composite microspheres were composed of TiO2 and SiO2, about 300 nm in diameter. TiO2 nanometer thin layer was uniformly deposited on the surface of SiO2 with Si-O-Ti bonds existed; The specific surface area of SiO2/TiO2 mesoporous composite microspheres was about 92.3 m2/g , approximately 3 times as big compared with the P25. Photocatalytic evaluation showed that the degradation of Rhodamine B rate for SiO2/TiO2 mesoporous composite microspheres reached 98%, improving significantly compared with P25.