Abstract: Bogie gearbox is an important part of metro vehicle transmission system. If its parts are abnormally worn and the generated metal powder enters into the lubrication oil circulation, it will lead to problems such as abrasive wear and fatigue pit on the gear tooth surface, and will also aggravate the bearing wear leading to poor operation. The causes of abnormal wear of oil distribution ring of bogie gearbox are analyzed. The assembly process of gearbox input shaft system is verified. The compression amount of input shaft end cover is modeled and calculated, and the causes of abnormal wear of oil distribution ring are discovered. On this basis, the corresponding optimization and improvement measures are put forward, which effectively solves the problem of abnormal wear of oil distribution ring of bogie gearbox.