Aiming at the early failure of oil seal in high-speed grease-lubricated rolling bearing,the thermal-stress coupled finite element model of oil seal was established,and the influence of main parameters of oil seal and working condition parameters of bearing on the maximum temperature and contact stress of oil seal lip were studied.The structural parameters of the oil seal were optimized and verified by the enhanced temperature-rise grease-leakage test bench.The results show that the influence of temperature should be considered in the study of oil sealing performance of high-speed grease-lubricated rolling bearing.The maximum temperature of seal lip increases with the increase of axial interference,hardness of rubber material,friction coefficient of sealing surface,bearing speed and temperature in bearing cavity.The maximum contact stress increases with the increase of the axial interference and the hardness of the rubber material,but changes little with the increase of the friction coefficient of the sealing surface,the bearing speed and the temperature in the bearing cavity.After the sealing structure optimization,the average grease leakage rate is reduced by 56.7% and the average temperature rise is reduced by 54.3%.