To provide a floor heating device to entirely eliminate a risk of a fire occurring and have excellent energy saving ability by a method wherein a heating medium container formed along an outer wall and composed of an upper pipe is sealed with corrosion resisting water (a heating medium), and an electromagnetic wave induction heating mechanism is arranged at a part of the container to heat corrosion resisting water.

A copper pipe 2 is laid on an outer wall 1 in a manner to form a closed circuit and sealed with corrosion resisting water 3, such as degassed water, ion exchange water, and distilled water, as a heating medium. An electromagnetic wave induction heating mechanism 4 is disposed at a part of the closed circuit of the copper pipe 2 and a moving pump 6 is fitted in a proper spot in the copper pipe 2. In arrangement of a corrosion resistant floor heating device, one surface or upper and under surface sides of a floor on which the floor heating device is placed are covered with an electromagnet wave shield material. By using corrosion resisting water in a state to seal the copper pipe 2 therewith, corrosion of the copper pipe 2 is completely suppressed and since a device is of an electromagnetic wave induction heating system, energy saving ability and rapid heating ability are improved.