The disclosed technology is directed to an endoscope comprises an endoscope body defined by an insertion portion and an operating portion both of which are a hermetically sealed structure with a predetermined gas pressure maintained in the endoscope body. The operation portion includes a ventilation inlet attached thereto to deliver a gas into the endoscope body and to hold the gas at the predetermined gas pressure in the endoscope body. A measuring unit is configured to be mounted on a board disposed in the operating portion for measuring a gas pressure in the endoscope body. A controller is configured to acquire a value measured by the measuring unit and to determine whether or not there is a gas leakage from the endoscope body based on the acquired measured value.
