Taking a certain type of 250 km/h EMU as the research object， a bearing-vehicle-track rigid-flexible coupled dynamic model was established， which considered the time-varying stiffness of the bearing， the flexibility of the wheelset， axle box and track. The development laws of bearing raceway load and fatigue life in the presence of measured wheel polygonization evolution were inves? tigated， and the influence mechanism of wheel polygonization on bearing load was revealed. The results show that the amplitude of wheel polygon wear grows with the increase of operating mileage， which causes the increase of maximum contact load of the outer raceway and the load standard deviation of the No. 8 and No. 9 raceways. The damage value of bearing per kilometer will also in? crease， up to 1.4×10?7， and the fatigue life continues to decrease. After the re-profiling， the maximum contact load of the outer race? way is reduced by 14%， the load standard deviation of the No.9 raceway is reduced by 56%， and the damage value of the bearing per kilometer is reduced by 39%. Re-profiling the wheel in time can thus obviously improve the raceway load environment and prolong bearing life. In addition， when wheel polygonization passing frequency is coupled with the local bending mode of the rail， the bearing load will be more severe. Therefore， the detection density of wheel irregularity should be appropriately increased after 150000 km run? ning for the EMU， and the wear amplitude of 14th， 15th， 25th and 26th order polygonization should be paid more attention.