Abstract: Objective As a byproduct of iron and steel smelting, steel slag has the advantages of large yield and good gel properties, which can effectively relieve the supply pressure of high-quality natural stone needed for transportation infrastructure construction in China. Method This article takes steel slag as the research object, which is a by-product of iron ore smelting. In view of the application of steel slag in asphalt concrete, the application situation of steel slag asphalt concrete and the improvement technology of stability are discussed. Result Compared with the developed countries, the overall development of steel slag asphalt concrete is slow, and the proportion of steel slag asphalt concrete application is low. The main reason lies in the bad stability of steel slag. Carbonation technology and microbial enhancement technology are more advanced and have great potential, which are in line with the implementation of China's dual carbon strategy. Conclusion It is suggested to strengthen the research and development of screening technology of high quality steel slag and overcome the technical problem of low carbonation efficiency of steel slag, so as to change the current situation that steel slag can not be used in asphalt concrete.