A planar heating element that is safe, has excellent durability and exhibits minimal unevenness of heating can be provided by equipping the planar heating element with: a sheet-shaped polymer resistor; at least one pair of electrodes that are disposed on one surface of the polymer resistor and supply power to the polymer resistor; electrically insulating substrates that cover the polymer resistor and the electrodes from both sides; a non-combustible heat conductive material that covers the heat-generation sections of the polymer resistor and the junction between the polymer resistor and the electrodes from both sides on the outside of the electrically insulating substrates.
