A lock device for an opening and closing body attached to a fixed body, includes a rotary member includes a rotary shaft and a lock member connecting portion rotatably connected to a lock member. A rotary member attaching part includes an upright wall erected from a lock member arrangement surface, which is a surface of the opening and closing body or the fixed body facing the lock member, and a rotation support wall continuously provided to the upright wall and arranged spaced from the lock member arrangement surface, and is provided integrally with the opening and closing body or the fixed body. The rotation support wall is formed with a bearing hole in which the rotary shaft is inserted. A retainer preventing the rotary shaft inserted in the bearing hole from coming off is provided between the bearing hole and the rotary shaft.