To eliminate defects of a conventional heating furnace, wherein distortion by expansion of heater elements in heating and contraction thereof in cooling is accumulated in the heater elements as curved sections of the meandering heater elements are fixed to a heat insulating material for a furnace wall, which causes projection of the heater elements from a groove in which the heater elements are disposed, the contact of the heater elements with each other, the contact of the heater element with a heated object in the furnace, and fracture of the heater elements by thermal fatigue in use of the heating furnace for a long time.

This heating furnace for high temperature is composed of the heat insulating material for the furnace wall, the heater elements disposed in multiple stages on a core-side face of the heat insulating material while separated from each other in the vertical direction, and respectively bent in the meandering shape at upper and lower ends, heat-proof insulating hooks connecting the meandering sections opposed to each other, of the heater elements vertically adjacent to each other, and not fixed to the heat insulating material, and a means for suspending the heater element of the uppermost stage.