An endoscope apparatus includes: an optical adapter provided with a discrimination capacitor and an endoscope configured to be detachably provided with the optical adapter at a distal end portion of the endoscope, and configured to include a reference capacitor which is arranged to be connected in series to the discrimination capacitor in a state where the optical adapter is mounted, a DC power supply which is connected in series to the reference capacitor, and a control circuit which calculates a capacitance of the discrimination capacitor on the basis of a voltage value at a connection point between the discrimination capacitor and the reference capacitor, so as to discriminate the kind of the optical adapter.
