Cylinder liner-piston ring is one of the most important rubbing pairs in diesel engines. Its normal operation ensures the high performance of the whole engine system. Previous researches have shown that the process of liner has a great impact on the friction characteristics of cylinder liner-piston ring. Large scale pits and slots in dimension at the liner inner surface were processed and the experiments were conducted on the test rig to investigate the influence of this procedure on the friction characteristics of cylinder liner-piston ring under different engine rotation speeds in this study. By the use of oil analysis and vibration analysis, the friction information of cylinder liner-piston ring assembly was obtained and the lubrication mechanism of the test was analyzed. Experimental results show that implementing proper process of large pits and slots on the inner surface of the piston liner could improve the friction performance of the cylinder liner-piston ring at high engine rotation speed.