To provide a bearing device for a wheel capable of improving durability of a seal and maintaining bearing performance for a long period of time.

A backup seal 13 is pressed in an outer periphery of an end part of an outer member 3. The backup seal 13 comprises a cored bar 14, and a seal member 15 integrally vulcanized and bonded to the cored bar 14. The seal member 15 is bonded from an inner end part 14d of the cored bar 14 to an inner peripheral face of a cylinder part 14c and a part of an inner peripheral face of a disc part 14b, and includes a seal lip 15a inclining and extending inward in a diameter direction. The seal lip 15a is arranged so that a slide-contact face is opposite to an approximately center of a side lip 12a and a slide-contact face of the side lip 12b.