There is disclosed a structure for fastening a shipboard-protecting fender comprising: a plurality of reinforcing rib layers securely provided on the inner and outer faces of a shipboard; a fixed base horizontally fastened on the reinforcing rib layers of the shipboard by means of a plurality of bolts, an accommodating space being formed at the outside of the fixed base; a core layer, one end of which is accommodated in the accommodating space of the fixed base; a bump-preventing layer covering the outer surface of the core layer and the fixed base; a pair of fixed plates supported at the outside of the two ends of the bump-preventing layer; and a plurality of bolts vertically passing through the fixed plates, the bump-preventing layer, the fixed base, and the core layer for fastening them, in which the bump-preventing layer is made from polyurethane (P. U.) material, while the core layer is made from the close cell of ethylene-vinylacetate copolymer (E. V. A) material, whereby the shipboard-protecting fender thus constructed may be especially suitable for the light weight requirement for fast ships, owing to features including not only wear resistance, light weight, but also durable firmness.