In order to investigate the enhancing effect of basalt fiber (BF) on toughness of asphalt, BF modified asphalt and mixture were prepared. Strip tensile test was performed to study the anti-cracking ability of BF modified asphalt. The effect of BF on toughness of asphalt mixture was investigated using MTS system. SEM was conducted to explore the enhancing mechanism of BF. The results showed that the ultimate tensile stress of BF modified asphalt peaked when fiber content reached 0.4% by weight of asphalt mixture. Composite materialization and self-healing force of BF led to the enhancing effect on toughness capacity of asphalt.