Selective catalytic reduction of nitrogen oxides using carbon monoxide is considered a promising technology due to a series of advantages. Three α-Fe2O3 catalysts for CO-SCR were prepared by hydrothermal, precipitation and sol–gel methods. A series of characterization studies were performed on these three catalysts. It was found that the catalytic efficiency of all three catalysts increased with increasing temperature, and the conversion rate reached 100 % after the temperature exceeded 250 °C. Under the same low-temperature reaction conditions, the Fe2O3-HT samples prepared by the hydrothermal method showed the best catalytic efficiency for NO, followed by the precipitation method, and the sol–gel method showed the worst catalytic efficiency. The best activity of Fe2O3-HT was probed by characterization due to its higher crystallinity resulting in higher surface Fe3+. Based on the TPD results, a possible mechanism for this catalytic reaction was inferred to be the E-R mechanism. Since CO-SCR technology has great potential and development prospects and the simplicity of the research method in this paper produced good results, it is a reference for the design of new CO-SCR catalysts in the future.