Abstract: Mixed oxides, Ti02-MeOx (Me-V, Cr, Mn, Fe, Co, Ni, Cu) have shown high catalytic activity for the NH3 decomposition reaction and the reduction of SO2 by NH3 to elemental sulfur. Co3O4-TiO2 and Fe2O3-TiO2 catalysts show higher catalytic activity than other catalysts at low temperature. Characterization by XRD indicates that transition metal sulfides are probably the most active. The mechanism of the reduction of SO2 by NH3 to elemental sulfur over Ti02-MeOx (Me-V, Cr, Mn, Fe, Co, Ni, Cu) catalysts is assumed.