In this study, we developed a novel combination model for different types of catalysts, which could generate synergistic effects for the catalysts with different functions. A Mn₃CeO_x catalyst with good low-temperature activity and a Ce_0.1TiO_x catalyst with good medium and high temperature activities were selected to make the combination and show synergistic effects. The combination of Ce_0.1TiO_x–Mn₃CeO_x (with Ce_0.1TiO_x located at the upstream of Mn₃CeO_x) showed high NO_x conversions in the whole temperature range, together with relatively low N₂O formation, indicated the synergistic effects between the Ce_0.1TiO_x and Mn₃CeO_x catalysts. This combination model can be extended widely to various NH₃-SCR catalysts and therefore has universal significance.