TiO2-SiO2 composite oxides were prepared by sol-gel method with TiOSO4 and sodium silicate as precursors.TiO2-SiO2 composite oxides were characterized by XRD，SEM，TEM，BET，laser particle size analyzer and UV-Vis.The influence of preparation condition on the physical properties such as crystalline phase，morphology，pore structure and particle size of TiO2-SiO2 composite oxides were investigated.The degradation properties of TiO2-SiO2 composite oxides in Rhodamine B solution under ultraviolet region were investigated.The results showed that TiO2/SiO2 composite oxides possessed an excellent photocatalytic activity which was obviously superior to that of commercial P25 TiO2.The calcination temperature had the greatest influence on the performance of catalyst.