The discharge situation of flue gas pollutant from two key processes of coking and sintering in iron and steel industry and the current environmental protection policies of iron and steel industry are analyzed in this study. Base on the analysis of the emission characteristics of flue gas pollutants from coking and sintering processes, and comparing the characteristics of flue gas of power plant, the technical route which can be improved by combining the flue gas treatment mode of power plant and its own characteristics. The environmental protection status of a large state-owned iron and steel enterprise was analyzed based on the desulfurization and denitrification equipment. The advantages and disadvantages of existing source emission reduction, process control and end-treatment technologies for typical pollutants such as sulfur dioxide, nitric oxides and particulate matter are analyzed. Furthermore, combining with the advantages and disadvantages of these technologies, three technical routes to achieve ultra-low emission of flue gas pollutants are put forward in the coking and sintering processes, that are semi-dry desulfurization combined with selective catalytic reduction denitrification, semi-dry/wet desulfurization combined with ozone oxidation denitrification, integrated desulfurization and denitrification of activated coke. This work emphatically introduced the application effect of these technologies in a large iron and steel enterprise, and based on the whole process coupling technology, the multi-pollutant collaborative removal technology and its application in coking and sintering processes were proposed respectively, that were low nitrogen combustion technology combined with terminal technology of multi-pollutant control technology of active coke and sintering flue gas circulation combined with activated coke multi-pollutant cooperative control technology. In the end, based on the application effect of technical routes in this work, the rationalization suggestions were put forward for selecting ultra-low emission technologies in sintering and coking processes of iron and steel industry in the future.