PURPOSE: To obtain a composite for a ship having high strength and elasticity and excellent impact resistance by using a woven fabric made of a polybenzazole fiber as a reinforcing material.

CONSTITUTION: A structure material for a ship is formed into a laminated plate of a sandwich structure having a composite plate as a shell made of a woven fabric as a reinforcing material consisting of a carbon fiber and a poplybenzazole fiber and a foamed polymer as a core. For the reinforcing woven fabric, a combination of a carbon fiber woven fabric and a polybenzazole fiber woven fabric, or a textile woven by mixing the two fibers is used. For a composite laminated woven fabric, an alternately laminated structure of the carbon fiber woven fabric and the polybenbzazole woven fabric is desirable. For the number of laminated layers, two or more laminated layers are laminated as occasion demands. Here, the polybenzazole fiber means a fiber consisting of a polybenzazole polymer. The polybenzazole means a plybenzoxazole homopolymer, a polybenzothiazole homopolymer and their random, sequential or block copolymer.