Abstract: Preparative methods of sol-gel，hydrolysis precipitation，hydrothermal synthesis for photocatalysts of TiO2-SiO2 composite oxide at home and abroad are introduced in this paper. The advantages and disadvantages of these three methods are also presented. The influence factors of adding silicon for enhancing photocatalytic activity is discussed. The results show that adding silicon can increase the catalysts’ specific area，raise the temperature of phase transition，and enhance surface acidity. It can also form Ti-O-Si band，which can reduce particle size and widen band gap. Finally，the future development in this field is presented.