In the present invention, an endoscope has a temperature sensor unit, a heating unit, and a control unit. The temperature sensor unit is provided at a front end part of an insertion part of an endoscope that can be inserted into a body cavity of a subject, said unit being configured to detect the temperature of the front end part and output the temperature as a temperature signal. The heater unit is capable of radiating heat for preventing clouding of an objective optical system provided at the front end part. The control unit detects the temperature of the front end part on the basis of the temperature signal and controls the generation of heat from the heating unit when a discrimination condition for discriminating whether the temperature of the front end part detected on the basis of the temperature signal is equal to or less than an predetermined temperature is satisfied.