To provide a temperature sensor in which a temperature in a temperature measuring part is extremely precisely detected, and the case where a pad part peels off from an insulating substrate and a lead terminal gets out of the insulating substrate is prevented even when a large external force is applied to the lead terminal hard-soldered to the pad part.

A temperature sensor is constituted by putting a temperature measuring part 2a and pad parts 2b connected to both ends of the temperature measuring part 2a onto the surface of an insulating substrate 1 together by baking, and hard-soldering a lead terminal 2 onto the pad part 2b. In this sensor, the temperature measuring part 2a comprises a metal with platinum contained as a main component, and the pad part 2b comprises a metal with molybdenum or tungsten contained as a main component. Thereby, the pad part 2b is tightly fix-bonded to the insulating substrate 1, and the case where the pad part 2b peels off from the insulating substrate 1 and the lead terminal 3 gets out of the insulating substrate 1 is prevented.