Abstract: Based on the compression of man-vehicle ration in metro overhaul and the control of human cost, Guangzhou metro Line 2 is taken as the engineering background, the fault data of vehicle door system repair and main line vehicle door in the past three years are collected. Then, by using the FMECA (failure mode effects and criticality analysis) method, the optimization of the vehicle door maintenance cycle is studied, in order to reduce the number of workers and improve the operation efficiency.