Abstract: Iron ore sintering serves as the primary emission source of nitrogen oxides (NO_x) in the iron and steel industry. The flue gas generated from this process features low temperature, high humidity and high sulfur content, and contains various toxic substances such as alkali metals and heavy metals, which put forward higher requirements for the working condition adaptability of denitration technologies and the comprehensive performance of catalysts. At present, non-rare earth-based NH₃-SCR denitration catalysts generally exhibit poor low-temperature activity, insufficient poisoning resistance and inferior industrial operation stability. These catalysts cannot meet the long-term ultra-low NO_x emission standards for sintering flue gas, which becomes a key bottleneck restricting the green and low-carbon development of the iron and steel industry. China is endowed with abundant rare earth resources. With unique 4f electron configurations, rare earth elements possess excellent redox properties and superior surface acidity regulation capability, which provides strong support for the performance optimization of SCR(Selective Catalytic Reduction)denitration catalysts. This paper systematically sorted out the multi-component pollution characteristics of steel sintering flue gas and the current status of industrial denitration treatment, and clarified the deficiencies of traditional denitration technologies in practical industrial application. The laboratory performance and industrial application limitations of various non-rare earth-based catalysts including V-Ti-based, Mn-based, Cu-based and Fe-based catalysts were analyzed. This study emphatically elaborated the technical routes, core advantages and action mechanisms of rare earth modification for different non-rare earth-based catalysts, and summarized the inherent defects of existing rare earth-modified catalysts. Focusing on the industrial application practices of rare earth-based SCR catalysts. This review verified their industrial application values and sorted out the practical operational problems. Finally, this paper analyzes the application prospects of such catalysts by combining practical factors including cost control and large-scale preparation.The research aims to provide theoretical reference and practical guidance for the large-scale engineering application of rare earth-based SCR catalysts applicable to the complex working conditions of sintering flue gas, and promote the realization of ultra-low NO_x emissions and the achievement of the "dual carbon" goals in the iron and steel industry.