The wheel hub unit has been developing from the original assemblage of a flange,a steering knuckle and two sets of radial bearings to the new one with an out ring,a flange and an ABS sensor and designed for driving wheel or non-driving wheel separately. The new design simplifies the wheel supporting frame,combining the knuckle,the flange with the outer ring,and the inner ring with the hub flange. It integrates the connection and driving fuction of hub flange and bolts with the bearing supporting fuction. With the high-performance non-disassembled structure,the product can be sealed forever.