A mounting structure for a temperature sensor, which detects the temperature of a wall surface. The mounting structure includes a groove formed in the wall surface and having an inlet from which the temperature sensor is inserted. The temperature sensor includes a main body, which has a temperature detection surface that detects the temperature of the wall surface, and a lead wire connected to the main body. A support supports the main body. A wire bender bends the lead wire of the temperature sensor extending out of the inlet to press the temperature detection surface of the temperature sensor against the wall surface with an elastic force of the lead wire that is produced when the lead wire is bent. A stopper restricts movement of the main body of the temperature sensor.