In order to study the effect of copper on the tribological properties of cylinder liner-piston ring,copper infiltration modification layers of different thicknesses were processed on the surface of cylinder liner material through the double glow ion infiltration technology.The RTEC multifunctional friction and wear tester was used to carry out the experiments under different loads and lubrication conditions.The friction coefficient during the test,the wear volume and wear surface morphology after test were acquired and analyzed.The effect of copper infiltration modification layer on the tribological properties of cylinder liner material and its mechanism were studied.The results show that the copper infiltration treatment can effectively reduce the friction coefficient of the cylinder liner-piston ring friction pair and reduce the volume of wear.The effect of friction reducing and wear resistance of copper infiltration modification layer is particularly significant under high load and dry friction conditions,the friction coefficient is reduced by 13.15% under high load and 30.86% under dry friction,and the maximum wear volume is reduced by 30.70% and 38.57%,respectively.after copper infiltration,the wear surface of cylinder liner-piston ring is smooth,and a lubricating film layer with high copper content is formed on the friction surface,which has the effect of friction reducing and wear resistance.