An endoscope apparatus includes an identification unit provided in each of a plurality of optical adaptors, an MMA connected in parallel to the identification unit, an MMA drive circuit that is provided in a main body portion and applies a drive signal for driving the MMA through a pair of conductive wires, a sine-wave generation circuit that is provided in the main body portion and applies an alternating signal to the identification unit through a pair of conductive wires in a state where any one of the plurality of optical adaptors is mounted at a distal end portion, and CPU that is provided in the main body portion and measures an input impedance of the pair of conductive wires at a frequency of the alternating current signal to perform individual identification of the optical adaptor mounted at the distal end portion based on a measurement result.