To overcome problems of a conventional waterproof sheet fixture, i.e., to prevent separation of a cover layer of the waterproof sheet fixture, the cover layer being formed of chloroethylene or the like and covering a surface of a substrate of the fixture, and to eliminate a possibility of slipout of the fixture due to corrosion and enlargement of a screw hole, the corrosion being caused due to employment of a steel plate as the substrate.

There is provided a new waterproof sheet fixture, according to which a metallic substrate 11 has a screw hole 12 and a plurality of through- holes 14 formed therein, and outer surfaces of the substrate 11 are covered with synthetic resin cover layers 15. Further, the cover layers 15 on the front and rear surfaces are connected together by connection portions 16 which are formed of a synthetic resin filled in the through-holes 14.