To provide a supporting device which enables shoes usable for a normal walking to be combinedly used with a sport apparatus such as a ski board, a roller skate or an ice skate.

This supporting device which is used for shoes related to sport apparatuses, includes a sturdy shell 11 which partially surrounds a shoe 2, 3, 4 to the rear section at the lower region, from the side direction. The sturdy shell can be inserted between an element to be engaged with a sport apparatus, and the shoe, and also, has a means to detachably lock the shell to the shoe.