Thermocouple-type temperature-detecting device

A thermocouple-type temperature-detecting device comprising a ceramic-made outer protective pipe, a ceramic-made front protective pipe fixed to the inside of the above-described outer protective pipe by a 1st fixing member such that a closed head portion thereof is projected to the outside from the outer protective pipe, a heat-resisting ceramic-made filler packed in the inside of the front protective pipe, a pair of alloy element wires each having a different composition, which are laid in the filler and constitute a temperature-measuring portion by connecting each other at the head portion side, a heat-resisting glass-made sealing member sealing an end portion of an open form at the opposite side of the front protective pipe to the heat portion, and a hollow rear protective pipe fixed to the outer periphery of the end portion of the open form of the front protective pipe by a 2nd fixing member and the inside of the hollow rear protective pipe disposed in the outer protective pipe is formed as an air layer through which the alloy element wires penetrate.