A hub unit is equipped with an inner member having an inner ring raceway formed on its outer peripheral face, an outer member having an outer ring raceway formed on its inner peripheral face, and a plurality of rolling elements provided between the inner ring raceway and the outer ring raceway. At least one of the inner ring raceway and the outer ring raceway has a rolling contact zone on which an induction-hardened layer is formed. The hardened layer has a depth of about 1.5 to 1.9 mm at a distance of 1 mm inward from each end of the hardened layer.