An anti-slip device provided with a supporting plate of metal or resin having an attachment portion on a reverse face for other members, and a rubber elastic body unitedly mounted on the supporting plate. Plural connection holes are formed from an obverse face to the reverse face of the supporting plate. Further, the rubber elastic body is composed of a receiving piece portion covering approximately whole of the obverse face and a falling-prevention portion from the reverse face to connect the receiving piece portion through a peripheral portion and the connection hole.