Abstract: The present invention provides a connecting structure for swingably connecting two parts such as adjacent pieces and the like of a band and comprises: a plurality of connecting pipes which are provided on the adjacent parts and aligned along the same axis; a connecting pin which is inserted into the connecting pipes; and a C-shaped spring ring which engages with an installation groove of said connecting pin in a manner such that the diameter of the spring ring can be reduced; wherein, together with the connecting pin, the spring ring is inserted into the connecting pipes by reducing the diameter thereof, and fastens the connecting pin to the connecting pipes by enlarging the diameter of the spring ring inside the connecting pipes until the outer surface of the spring ring contacts the inner surface of the connecting pipes.