An endoscope apparatus according to the present invention is featured by including: an endoscope which has a connector main body; an apparatus main body to which the connector main body can be detachably mounted; a closed space which, after the connector main body is mounted to the apparatus main body, is formed in exterior housings of the apparatus main body and the connector main body by being closed by the exterior housings; a heat generating portion which is provided in the closed space; and a fan which is provided in the closed space, and performs at least one of dissipation of heat of the heat generating portion to the closed space and transfer of heat in the atmosphere in the closed space to the exterior housing.