Abstract: The present invention provides a connecting structure for plate members, including a projection projected from one of the plate members in a first direction, and a groove provided on the other of the plate members to have inner faces facing each other in a second direction intersecting the first direction and configured to fittingly receive the projection. The projection includes a main body, a resilient portion provided on one side of the main body in the second direction and resiliently inwardly deformable in the second direction, and an engagement portion outwardly expanded in the second direction from the resilient portion and configured to be plastically deformed along and engage with one of the inner faces of the groove when the groove fittingly receives the projection.