Abstract: The ultrahigh molecular weight polyethylene (UHMWPE) composite modified by nano-SiO2 particles and glass microballoons was prepared by compression molding. The effects of relative sliding speed, load and glass microballoon content on friction and wear properties of the composite were studied, and the wear morphology and mechanism were analyzed. The results show that adding nano-SiO2 particles and glass microballoons could enhance the hardness, compressive elastic modulus and friction and wear properties of the composite. The relative sliding speed had a great effect on friction coefficient and wear rate of the composite, and the effect of load on friction coefficient of the composite was not obvious, but the wear rate increased with the increase of load. The main wear mechanism of the composite modified by nano-SiO2 and glass microballoons was adhesive wear and fatigue wear.