Steel slag is not included in the latest alternative raw materials for cement production mixtures，and it is urgent to find a new way of bulk utilization. The content of alkaline oxides such as CaO in steel slag is high，and steel slag can be used to replace part of the sintering flux. Through the study of the properties of sintered raw materials and slag，the sintering cup test is carried out on the steel slag tailings with different proportions in the laboratory，and its mechanism is analyzed. The results show that when the amount of steel slag tailings is increased from 0 to 2% ，it has little effect on the soft melting properties of sinter，and the reduction degree and low-temperature pulverization are enhanced. And the content of calcium ferrite has been further improved，and has good strength and good reducing performance. During the sintering process，there is an interlaced network structure between calcium ferrite and magnetite，which improves the strength of the sinter. The CaO in steel slag tailings participates in the liquid phase reaction，and the liquid phase amount is better than that of Ca( OH) ₂ group，because the steel slag tailings contain SiO₂，when the SiO₂ content increases，the low melting point compounds of olivine increase accordingly，which leads to the enhancement of fluidity. According to the sintering cup test，the optimal process parameters are determined to be that the steel slag tailings ratio is 2% ，and the particle size of steel slag tailings is controlled at less than 3 mm，and the sintering performance reaches the best.