Abstract: The artificial ?oint material of UHMWPE composite filled with nano –ZrO₂ in different contests was prepared with a pressing formation method Hardness and shear punch behavior of ZrO₂ / UHMWPE composites were measured with UMT tribo -tester Biotribological behavior of the composites was investigated with a hip joint simulator under lubrication of caU bovine synovial The experimental results indicated that nano –ZrO₂ filler increased the hardness , frature load and fracture work of composites , and reduced the wear rate of the composite The sizes of the wear particles become larger as the ZrO₂ contents increased The wear resistance of UHMWPE composites was influenced by their severe -deformation behavior A negative linear function was found between the wear rate and fracture load , fracture work