PURPOSE: To prevent separation from taking place between a hub and a driving shaft caused by released joint by welding, in a bearing for connecting the wheel to the driving shaft of vehicle.

CONSTITUTION: A rolling bearing is constituted between an inner wheel 11 formed by connecting a hub member 1a and a driving shaft member 2a to each other and an outer wheel 12 formed on a knuckle 4, and the hub member 1a of the inner wheel 11 and the fitting part of the driving shaft member 2a are welded and joined with each other. A stop wheel 8 is assembled into inner circumferential grooves 6, 7 provided on the fitting surface of the hub member 1a and the driving shaft member 2a, and slipping-out of the hub 1 and the driving shaft 2 is stopped by the engagement of the stop wheel 8.