PURPOSE: To expand the utilization field by laminating an adhesive nonvulcanized rubber sheet on the back face of a cork layer or providing a cover layer such as rubber or synthetic resin on the surface and laminating the adhesive nonvulcanized rubber sheet on the back face.

CONSTITUTION: A self-sticking adhesive nonvulcanized rubber sheet 1 kneaded with adhesion applying resin, a softening agent, an antioxidant, a filler material or the like is laminated and formed on a cork layer 2 of a cork sheet itself made by cutting the bark of cork oak or Quercus variabilis into a plate shape. A cover layer 3 made of rubber, synthetic resin or the like is provided on the surface of two layers of the rubber sheet 1 and the cork layer 2 or on the surface of the cork layer 2, the rubber sheet 1 is laminated and formed on the back face. The warping, protrusion, bulges or the like after the construction can be thereby prevented during the cork plate construction.