Abstract: This endoscope apparatus is provided with a plurality of kinds of endoscopes each having an elongate insertable part having an illuminating window and observing window in the tip part. An illuminating light transmitting system leads an illuminating light to the illuminating window. An imaging apparatus receives the returning light from an object entering from the observing window and imaging the object. A signal transmitting system is connected at one end to the imaging apparatus. An illumination connector is provided at the entrance side end of the illuminating light transmitting system and is different in at least one of the illuminating method and signal processing system. The endoscope apparatus is further provided with an illuminating apparatus having an illumination connector receptacle removably connectable with respective illumination connectors of the plurality of endoscopes and feeding illuminating light to the plurality of endoscopes.