Wheel bearing device

A wheel bearing device comprising:

• a wheel bearing including an inner member having double row inner raceway surfaces and a flange portion for being attached to a wheel, an outer member having double row outer raceway surfaces, and a plurality of rolling elements disposed between the inner raceway surfaces and the outer raceway surfaces facing each other;
• and
• a constant velocity universal joint having an outer joint member, the outer joint member and the inner member being coupled so as to be able to transmit torque by meshing face splines respectively provided in the outer joint member and the inner member and applying a tightening force in an axial direction between both the face splines, wherein
• shapes of tooth surfaces of both the face splines are determined such that, in a process of bringing both the face splines close to each other in the axial direction and meshing with each other, the tooth surfaces of both the face splines first come into contact with each other in, among an outer diameter portion of a meshing region between both the face splines, an inner diameter portion, and an intermediate portion sandwiched between the outer diameter portion and the inner diameter portion, one of the outer diameter portion and the inner diameter portion, and then the tooth surfaces of both the face splines come into contact with each other in the other.