A wheel hub unit comprises a wheel hub body (100, 200), a first tapered roller bearing (101, 201) and a second tapered roller bearing (102, 202). Two bearings are oppositely disposed in the wheel hub body (100, 200). A bearing bush (104) or a shaft sleeve (204) is sleeved in the inner rings of the first tapered roller bearing (101, 201) and that of the second tapered roller bearing (102, 202), so as to form a rolling and sliding bearing, and the high strength load is effectively absorbed. A seal element is disposed between the outside end of the bearing and the wheel hub body (100, 200) to form the integral type independent seal. The problem that the inner rings of the bearings are exchanged and assembled in a mixed way during the assembly process is avoided, and the efficiency and accuracy of assembly are improved.