Axle assembly for driving wheel of vehicle

An axle assembly for a driving wheel of a vehicle, comprising:

• a shaft rotated by receiving driving force from a powertrain and configured to rotate a wheel disc connected thereto;
• an axle housing disposed to pass through a center of a steering knuckle connected to a steering apparatus, and coupled to the shaft through a joint so as to be rotated integrally with the shaft, wherein the axle housing is fixed to the wheel disc and coaxially disposed with the wheel disc;
• a wheel bearing mounted between the steering knuckle and the axle housing;
• a joint bearing mounted on an outer part of the shaft so as to be spaced apart from the joint by a designated distance;
• and
• a boot unit configured to have a first end coupled to an outer race of the joint bearing and a second end coupled to an outer race of the wheel bearing so as to form a space filled with a lubricant outside the shaft.