To provide an electric furnace capable of decreasing heating element capacity and decreasing electric consumption of the heating element by combinedly using heating with high temperature gas and heating with the heating element.

This electric furnace has an outer furnace casing 5 surrounding the outer surface of an inner furnace body 4 through a combustion gas path 8. The heating element 9 is set at inside of the inner furnace body 4. The high temperature combustion gas is flown in the combustion gas path 8 concurrently with energizing the heating element 9 so as to heat-from outside and to perform temperature compensation for heatup performed by the heating element 9.