Abstract: Reaction characteristics of the oxidation of SO2 with vanadium catalyst in molten liquid phase was studied. A new mechanism was proposed for this liquid phase reaction. Based on the proposed mechanism, an intrinsic rate model was derived. Taking the effect of mass transfer in the liquid intoconside ration avoiding the tedious solution of the effectness factor, a"micro-kinetic" models relating to the intrinsic rate model were formulated. It was further pointed out that different model were necessary for different levels of temperatures. In the development of the macrokinetic models for the SHU commercial catalyst pellets, simplified models for porous diffusion were used. Experimented data regression suggested that the macrokinetics models over the different temperature ranges could be written as follows, At higher temperature levels (460-580℃): and at lower temperature levels(400 -460℃):