BEARING DEVICE FOR A WHEEL

Provided is a bearing device for a wheel capable of suppressing radial play and allowing firm and easy connection between a hub and an outer ring of a constant velocity universal joint. Axially extending projections are provided on a shaft portion of a joint outer ring, and the shaft portion is press-fitted into a hole of a hub. Through this press-fitting, recesses held in close fit-engagement with the projections are formed by the projections in an inner diameter surface of the hub, forming a recess/projection fit-engagement structure in which the projections and the recesses are held in close contact with each other over an entire f it-engagement region thereof. A press-fitting margin d of the projections with respect to the hub and a height h of the projections are set to the following range: 0.3 < d/2h < 0.86.