To provide a supporting structure capable of successfully supporting a knuckle on a bearing and making the supporting structure which is light-weighted and inexpensive.

The supporting structure of the bearing 20 supports the bearing 20 to support an axle shaft in a bearing support 2 of the knuckle 1, and comprises a bearing bush 10 pressed into the bearing support 2. The bearing bush 10 is pressed into the bearing support 2. The bearing 20 is pressed into the bearing bush 10.