In order to explore the influence of steel slag coarse aggregate on the road performance and volume stability of asphalt mixture,two different expansive steel slags were used as coarse aggregates and the limestone was used as fine aggregates to design the mix as AC-13C type asphalt mixture. The influence of steel slag on the performance of asphalt mixture was analyzed by immersion Marshall test,dynamic stability test,freeze-thaw splitting test,indirect tensile test and volume stability test. X-ray diffraction (XRD) and scanning electron microscope (SEM) was conducted to investigate the mechanism. The results showed that the road performance of steel slag asphalt mixture is better than that of limestone asphalt mixture. The indirect tensile fatigue properties of steel slag 1 and steel slag 2 asphalt mixtures were 1.36 and 2.16 times that of limestone asphalt mixture,respectively. The asphalt mixture produced with steel slag 2 had better stability than steel slag 1. Although the volume stability of steel slag asphalt mixture decreased,the Marshall stability of steel slag 1 and steel slag 2 asphalt mixture was still 1.25 times and 1.52 times higher than that of limestone asphalt mixture after 72 hours of immersion.