To prevent a temperature-sensitive part of a dial-thermometer for measuring the winding temperature of a mold transformer from being dislocated and broken by vibration or the like generated during operation of the mold transformer.

A winding temperature measuring device includes: a temperature-sensitive part fixture 502 by which a temperature-sensitive part 203 of a dial-thermometer fixed to a core fastening metal fitting 103 of a mold transformer 1; a conduit fixture 503 by which a portion close to the temperature-sensitive part of a conduit 206 connecting a temperature-sensitive part 203 with a temperature indication part 205 is fixed to the core fastening metal fitting 103 at a position separated by a predetermined distance therefrom and between the conduit fixture 503 and the temperature-sensitive part 203. A portion extending between the conduit fixture 503 of the conduit 206 and the temperature-sensitive part 203 is loosened in an S-shape.