The fretting wear tests of TC4 titanium alloy against GCr15 and Si3N4 were performed under different loads using an Optional SRV-IV oscillating wear tester,and the effect of counterpart materials on fretting wear behavior of TC4 titanium alloy was studied for the proper application of counterpart materials to reduce the fretting wear of TC4.The results show that it is better to choose Si3N4 ceramic with higher hardness as friction pairs of TC4 titanium alloy under low load,while it is more ideal to choose GCr15 steel as friction pair under high load.The wear mechanism of TC4 titanium alloy against GCr15 steel is abrasive wear and fatigue wear and the wear rate is decreased with the increasing of the load.During the friction process of TC4 titanium alloy against Si3N4 ceramic,the formation of wear debris is accompanied by the hydration of silicon,which increases the stickiness of wear debris.Under low load,the wear debris is easily bonded to form a dense third body covering on the surface of TC4 titanium alloy,which plays the role of lubrication,bearing and isolation of friction pairs.While under high load,the third body layer is unsticked from the surface of TC4 titanium alloy because of the abrasive wear and adhesive wear,and the friction coupling comes into contact with each other directly,which leads to the wear rate increase.