WHEEL BEARING DEVICE

A wheel bearing apparatus for rotatably supporting a wheel includes: an inner member 10 having two rows of raceway grooves 16a, 16b on an outer circumference thereof; an outer member 30 having two rows of raceway grooves 36a, 36b on an inner circumference thereof; and a plurality of rolling elements 28a, 28b interposed between the raceway grooves 16a, 16b of the inner member 10 and the raceway grooves 36a, 36b of the outer member 30. The raceway grooves 16a, 16b of the inner member 10 and the raceway grooves 36a, 36b of the outer member 30 are formed by hardened steel cutting. In relation to at least the raceway groove 16b on the outboard side out of the raceway grooves 16a, 16b of the inner member 10, h/d exceeds 0.50 where h is the depth of the groove and d is the diameter of the rolling elements. This provides a wheel bearing apparatus being compact and capable of withstanding a high applied load without inviting an increase in the size of the bearing.