To reinforce a concrete product or structure, by bonding a resin obtained from an ordinary temperature radical reactive compound with a reinforcing layer made of aramid resin and integrally forming them.

An ester acrylate resin which reacts and cures in an ordinary temperature is used as a primer and a resin for immersion and a sheet made of aramid fiber is used as a fiber sheet. And unsaturated polyester resin is obtained from an ordinary temperature radical reactive compound and vinyl ester resin is obtained an ordinary temperature radical reactive compound of a composite compound. In this case, the tensile strength in one direction of a reinforcing layer is set 50 kg/cm or higher. And further, the weight of the aramid fiber per unit area of the reinforeing layer is 50-1000 g/m2. In this way, a layer selected from textile, nonwoven cloth, woven material, paper-like material, honeycomb-form material, filmy material, etc., can be used to easily and rapidly reinforce or repair a concrete face.