A sealed anchoring dowel for a supporting material. The anchoring dowel adapted for being introduced in a supporting material, going therethrough, comprises an axial through-hole (6, 6.1) for receiving a member for fastening a part to be fastened to the supporting material. Advantageously, it comprises sealing means (14) arranged in the axial through-hole of the body, so as to obstruct the space between the internal wall of the body and the fastening member (7, 7.1).