The objective of the study is to find out a kind of suitable way of establishing load spectrum on durability test of the car hub bearing. On the basis of establishing the car dynamic model, the paper analyzed the load situation of the Hub bearing. According to the ordinary transport status of the actual car, the driving cycle of the car was set up. In the end, the steps of establishing load spectrum were given out, and the paper took SANTANA car for example to make out its load spectrum on durability test. Compare with the traditional way of establishing load spectrum, the way can make load spectrum to close the practical load of the car hub bearing.