Abstract: Surface strengthening of heat-treated Ti-6Al-4V alloy was carried out by ultrasonic rolling process(URP), and the changes of the microstructure and fretting friction properties of surface layer of the heat-treated Ti-6Al-4V alloy after ultrasonic surface rolling were analyzed. The results show that the heat treatment process significantly increases the proportion of α phase, the microhardness is increased to 345 HV, and the yield strength of the material reaches 886 MPa. After URP treatment, the microhardness is increased to 457 HV, the residual stress value is decreased to-725 MPa, and the surface roughness of the material is decreased to 0.17 μm. The minimum grain size of material surface layer is sub-micron. The heat-treated sample shows the lower CoF and smaller wear area after URP treatment. This indicates that the heat-treated material after ultrasonic rolling has better wear resistance.