A series of WO3/TiO2 catalysts with different W loading were prepared by impregnation method, and the effects of W loading, temperature and SO2 concentration on the SO2 oxidation process on the catalysts were investigated. The results show that the SO2 oxidation rate on the catalyst surface increases with the increase of W loading and temperature. The SO2 oxidation rate increases from 0.034% to 0.210% when the W loading is increased from 1% to 7%, and the SO2 oxidation rate increases from 0.043% to 0.240% when the temperature is increased from 280 ℃ to 400 ℃. N2 adsorption, X-ray diffraction (XRD), Raman analysis (Raman), NH3 programmed temperature (NH3-TPD), H2 programmed temperature (H2-TPD), X-ray photoelectron spectroscopy (XPS) were used to characterize catalyst properties. The results illustrate that the increase of W leads to the increase of WOx, which can weaken the strength of Brnsted acid site and enhance the adsorption of SO2. The oxygen (Oα) adsorbed on the catalyst increases considerably upon the content of W loading, which is not beneficial to reducing the oxidation of SO2. The in-situ FTIR results of 5% W loading show that SO2 will react with the W—O—W structure and be oxidized to HSO-4, and W6+ will be reduced to W5+ after the introduction of SO2. During the reaction, O2 does not directly oxidize SO2, but reacts with intermediate products to regenerate W—O—W, which makes W5+oxidized to W6+again.In addition, O2 promotes the conversion of HSO-4 to adsorbed SO3, while promoting the desorption of SO3 on the catalyst surface.