To provide a bearing device for a wheel with an extended service life including a bearing having enhanced sealability and durability.

The bearing device includes a seal 8 having a core bar 15 and a sealing member 16 integrally joined to each other. The core bar 15 has a fitting portion 15a internally fitted in the end of an outer member 10 and an inside portion 15b bent and extended inward in the radial direction from the fitting portion 15a. The sealing member 16 has a plurality of side lips 16a and 16b. The base portion 17 of a wheel fixing flange 4 is formed to have an arch-shape curved plane in cross section. The plurality of the side lips 16a and 16b slidingly contact with the base portion 17 at a predetermined interference. The inside portion 15b of the core bar 15 contains an inner end edge 15c having an inclination angle to the tangential direction of the curved plane of the base portion 17. The sealing member 16 goes around the inner end edge 15c to be fastened there. The inside end edge 15c is opposed to the base portion 17 via a predetermined gap in the radial direction. Thus, a labyrinth seal 18 is formed between the inside end edge 15c and the base portion 17.