Abstract: Based on the data statistics of wheel set, brake shoe wear and wheel set diseases on Guangzhou metro Line 8 after the split with Line 2, the previous test results are summarized, the impact of different braking parameters on wheel set, brake shoe wear and wheel set diseases is analyzed. On the basis of quantitative cost analysis, the optimal braking parameter program at this stage is obtained. In addition, the follow-up optimization ideas and directions are further proposed. The optimization of the braking parameters has effectively reduced the wear of wheel set and brake shoe, as well as the wheel set diseases, achieved the goal of saving maintenance cost.