To improve the anti-cracking property of steel slag-asphalt mixture (SAM), and minimize the effect of steel slag (SS) expansion characteristics on the durability of asphalt mixture， the comparative research on the effects and reinforcement mechanism of different contents of basalt fiber (BF) on the high and low temperature performance, water stability and fatigue property of SAM was implemented via rutting test, SPT dynamic modulus test, low temperature bending test, freeze-thaw splitting test, bending fatigue test, SEM test, etc. Results show that the addition of BF improves the high temperature anti-deformability, and increases the low temperature flexibility of SAM with different SS content to a certain extent. With the increase of freeze-thaw cycles, the decrease of water stability of BF-SAM is significantly lower than that of ordinary SAM. The reinforcement and crack resistance of BF improve the fatigue life of SAM. After comprehensive consideration of various road performance, the recommended BF content of BF-SAM is 4% （mass fraction） and the recommended SS content range is 45% to 55% （mass fraction）.