Abstract: Supported Co-Mo catalyst was prepared by impregnation-precipitation method using modified activated carbon as carrier and urea as precipitant.Catalytic activity of catalyst was studied by using the reduction of SO₂ by CO.Under optimum reaction conditions (sulfidation temperature 500℃; GHSV=7 000 mL·g^-1·h^-1;CO/SO₂ mol ratio =2:1; reaction temperature 450℃), the best catalytic activity and selectivity were obtained for Co-Mo catalyst with calcination temperature was 500℃ and Co/Mo mol ratio =0.45. Catalyst samples were characterized by X-ray powder diffraction (XRD) in order to relate the phase composition to the activation behavior and catalytic performance.The active phases of catalyst were detected as CoS₂ and MoS₂,and the formation of them were greatly dependent on the sulfidation temperature.And the catalytic activity of cobalt molybdenum catalyst decreased less than 1% after the reaction lasted for 24 h.