In order to accurately analyze and predict the bending fatigue life of a car hub bearing,considering the relationship between clearance and oil film thickness,as well as the influence of temperature on clearance and oil film thickness under the operating condition of the bearing,the minimum oil film thickness value was accurately calculated by combining the calculation method of point contact elastomeric oil film thickness.According to the correction method provided by ISO for Lundberg-Palmgren life model,the correction coefficient was determined and the improved life model was established.In order to verify the correctness of the improved model,a fatigue test was conducted using a rotating bending fatigue life tester,and the test results were within a reasonable error range,which proved the reliability of the research model.A hub bearing load distribution analysis model was established to discuss the effect of center distance on the maximum rolling body load.The variation law of fatigue life of hub bearings with the center distance under different pure bending moment loads and different vehicle speeds was studied.The results show that the moment load is the main factor affecting the fatigue life,and the bearing life can be extended by increasing the center distance.Bearing lubrication conditions are related to the bearing speed,and within a certain range,the higher the speed,the more adequate its internal lubrication and the longer the service life.