To provide a flat-shaped heating element having excellent mass- productivity, naturally enabled to prevent generation of poisonous gas at incineration, and enabled to surely dispose and stick a covering material of resistance heating wires to an adhesion film by thermal fusion of an insulation covering of a the resistance heating wire made of polyolefin group heat-resistant resin material by sticking the adhesion film made of polyolefin group thermosetting resin on the upper surface of a sheet-shaped metal foil, by the above, bridging treatment is disused, and enabled to aim at cost reduction.

For the flat-shaped heating element, an adhesion film 3 made of polyolefin group thermosetting resin is stuck on the upper surface of a sheet- shaped aluminum foil 2, and resistance heating wires 4 are arranged on the upper surface of the aluminum foil 2 in parallel rows by sticking insulation coverings 4a, 4b of the resistance heating wires 4 made of polyolefin group heat-resistant resin material to the upper surface of the adhesion film 3, by the above, a generation of poisonous gas at incineration is eliminated, and the adhesion of the insulation coverings 4a, 4b of the resistance heating wires 4 to the adhesion film 3 on the upper surface of the aluminum foil 2 is stabilized.