Abstract: The Beijing-Tianjin-Hebei Region is the most concentrated area of China's steel industry and one of the key areas for air pollution control. Analyzing the cost-benefit of medium- and long-term pollution control measures adopted in the Beijing-Tianjin-Hebei Region's steel industry is significant for selecting the most economical and effective emission reduction route and for improving the atmospheric environmental quality in this area. In this study, we built a comprehensive model including energy, environment and health assessment and designed four policy scenarios for cost-benefit analysis including scale-structure, scale-technology, scale-end, and comprehensive emission reduction. Then, we calculated the cost and benefits of the emission reductions of major pollutants (SO₂, NO_x, PM₁₀, PM_2.5, CO₂) in the steel industry in the Beijing-Tianjin-Hebei Region under the four policy scenarios from 2015 to 2030, and obtained the optimal route plan for pollution control and emission reduction by comparing the results. The results show that: (1) The scale-end had the lowest cost, which was only 15.18% and 23.94% of the scale-structure and scale-technology, respectively; the comprehensive emission reduction had the greatest potential for pollution reduction but the highest comprehensive cost. (2) The benefits assessed by the population health benefits method were much higher than the results derived from the environmental tax method, indicating that pollution reduction had higher potential population health benefits. Through the two benefits evaluation methods, the benefits under the comprehensive emission reduction scenario were 10.78×10⁸ and 76.14×10⁸ RMB, respectively, which were higher than other scenarios. (3) Based on the calculation of cost-benefit ratio, the ranking of comprehensive benefits was: scale-end scenario (0.46) > scale-technology scenario (0.24) > comprehensive emission reduction scenario (0.15) > scale-structure scenario (0.10) through the environmental tax method, and scale-end scenario (8.35) > comprehensive emission reduction scenario (1.07) > scale-structure scenario (0.57) > scale-technology scenario (0.65) through the population health method, indicating the emission reduction path of the scale-end governance scenario was the best. According to above results, the steel industry in the Beijing-Tianjin-Hebei Region should comprehensively assess the potential, costs and benefits of emission reductions based on the targets of regional environmental quality, and give priority to scale-to-end management when selecting the optimal path for synergistic emission reduction.