To provide a coupling device less in failure with a simple constitution and a wheel supporting device fitted with the coupling device.

The wheel supporting device is equipped with a rotary disc 20, a spring mechanism 30 installed between the rotary disc 20 and a wheel 10, a first supporting member 50, a second supporting member 60, and a rubber bushing assembly 40 (coupling device) interposed between the supporting members 50 and 60 and a suspension mechanism 70. The rubber bushing assembly 40 has three rubber bushings 41-43. Each bushing is composed of a rubber layer in cylindrical shape and an outer cylinder and an inner cylinder fixed to the outside and inside surfaces of the layer, respectively.