Cu-matrix/graphite composites with different aluminum content were fabricated by means of cold pressingsinteringrepressing technology under 900 ℃.Effects of aluminum content on tribological properties and wear mechanism of composites under dry and wet conditions were studied.The results show that the increase of aluminum is beneficial to enhance the hardness and bending strength of composites,while the relative density of composites is increased firstly and then decreased.Under the conditions of dry and wet friction,the wear resistance of the composites with higher aluminum content is enhanced greatly,because the composites with higher aluminum content have higher strength,which can help to resist asperities plowing and hold more graphite,and also can separate the metal matrix from the counterpart.The spalling and abrasive wear becomes weaker and oxidation wear is heightened because of the increase of materials’ strength after adding aluminum.Besides,water can promote oxidation wear of the composites in wet friction system.