A ceramic heater is proposed in which in the vicinities of the heating element's terminals where a bolt and a washer are used to fix and effect the electric supply connection to the heating element, the cover layer which covers most of the heating element is flush with an immediately neighboring part of the heating element layer so that the cover layer is not stepped at its edge and thus the washer does not scratch or otherwise damage the cover layer; a preferred embodiment adopts an electrically conductive protective film which is laid on this flush plane covering an area extending from the bolt hole to substantially beyond the line where the cover layer meets with the heating element layer.