To facilitate positioning correcting work and adhering work for a heating unit, a radiating plate and a toilet stool seat surface plate to the inner surface of the toilet stool by disposing the heating unit having an electric insulating layer in the periphery thereof through a radiating plate having heat fusion adhesive layers on both surfaces on the inner surface of a toilet stool seat surface plate formed of a thermoplastic resin.

In constituting a heating toilet stool seat unit, a heating unit 3 having an electric insulating layer 35 in the periphery thereof is fitted to a radiating plate 2, one side of which is covered with a thermal fusion adhesive layer 21, the other side being covered with another thermal fusion adhesive layer 22. That is, a toilet stool seat surface plate 1, the radiating plate 2, and the heating unit 3 are integrally fixed in order to the inner surface of the toilet stool surface plate 1 by thermal fusion by the thermal fusion adhesive layers 21, 22 of the surfaces of the radiating plate 2. The thermal fusion adhesive layers 21, 22 on both surfaces of the radiating member 20 are formed of resin materials respectively having the substantially same melting, so that thermal fusion of the toilet stool surface plate 1, the radiating plate 2 and the heating unit 3 is enabled by one heating. The radiating plate 20 is a magnetic film formed of a resin film containing a conductive material such as aluminum foil and a magnetic substance such as iron powder.