Ultra fine SO2-4/TiO2-SiO2 complex catalysts were synthesized by the one-step calcination method，which used titania sulfate and white carbon as raw materials and polyvinyl alcohol as dispersing agent. Catalysts are characterized by XRDIRTDA and BET. Different preparation factors were discussed.The catalysts consisting of SO2-43.4% and TiO2∶SiO2=1∶6 showed excellent reaction activity and stability for the photocatalytic degradation of phenol.Controlling calcination temperature and time (450 ℃

2 h) could avoid or diminish the formation of Ti-O-Si bond and obtain higher Vg and better dispersivity of TiO2 on the surface of SiO2.The kinetic study on photocatalytic degradation of phenol with the complex catalysts in a suspension system under 40 W UV-lamp showed that apparent rate constant k conformed to a zero-order kinetic model at initial concentration <100 mg8226;L-1 and increased with increasing pH value of phenol solution up to pH=12.When pH=10

k=3.32×10-1 mg8226;L-18226;min-1. Solar photocatalytic experiment also gave good results.