An endoscopic device includes a proximal side contact portion coming into air-tight contact with an outer peripheral portion of the insertion section, and a cavity is defined between the insertion section and a fixed member to a distal direction side of the proximal side contact portion. In a protruding state of a hood, a first path which makes an inside of the hood communicate with the cavity is defined, and the hood is in air-tight contact with the fixed member over an entire circumference in circumferential directions at a distal side contact portion. In a housed state of the hood, a second path which makes the cavity to communicate with an outside of the fixed member is defined.