To provide a ceramic heater which is better in the durability of an ion current detecting electrode portion and which can be manufactured at a low cost. A ceramic heater 1 is provided with: an insulating ceramic substrate 13; a resistance heating element 10 buried in the insulating ceramic substrate; and an ion current detecting electrode portion 14 formed integrally with the resistance heating element in the insulating ceramic substrate and having its own surface portion exposed as an ion current detecting face to the surface of the insulating ceramic substrate. The ion current detecting electrode portion 14 is constructed, at its portion including at least a portion of the ion current detecting face 15, of a conductive ceramic phase which is composed mainly of non-metallic conductive ceramic having a cation component made of a nonmetallic element, such as silicon carbide.