Effects of reaction temperature, processing time, Fe2(SO4)3 concentration and the particle size of coal on desulfurization of three kinds of high sulfur coals through heat treatment of Fe2(SO4)3 solution were investigated. The change of coal physicochemical property before and after the treatment was studied. The results showed that the highest removal of pyrite sulfur reached 67% while no significant change in the organic sulfur was observed when the concentration of Fe2(SO4)3 was 1 mol/L, the reaction temperature was 90 ℃, and the particle size of coal was less than 0.096 mm. The removal rate of total sulfur and pyritic sulfur increased upon increasing the reaction temperature, the concentration of Fe2(SO4)3, and the reaction time but decreasing the particle size of coal. The caking index of coal decreased at different degrees after the treatment, especially for Xinyu coal who lost the caking property totally. The inorganic sulfur was oxided into SO2-4 and removed due to the strong oxidability of Fe3+.