In view of the present situation of the research on the surface modified basalt fiber(BF) in China, and to improve the reinforcement and reinforcement effect of BF in asphalt mixture, silane coupling agent(KH550) was adopted in BP surface treatment, and a set of device which suitable for KH550 surface treatment BF was developed. The mechanism of KH550 surface modification BF was studied by infrared spectroscopy, scanning electron microscopy and X ray energy spectrum, the research has shown that KH550 solution can significantly improve the surface properties of BF, and the formation of the bump with stable chemical bond can significantly enhance the cohesion of the asphalt. Road performance of modified BF were studied which adopted the heat resistance, the retention ability of asphalt and segregation dispersion test, the study showed that the performance of KH550 surface modified BF was improved, which was beneficial to the performance of the asphalt mixture.