The endoscope apparatus 1 includes an endoscope connector 20, a first optical connector 51 extending from the plug part 41, a first insertion port 71 of a receptacle part 31 into which the first optical connector 51 is inserted , 76, the second insertion ports 72, 77 of the receptacle part 31 into which the second optical connector 52 is inserted, and a part of which are disposed in the second insertion ports 72, 77, and the first insertion port 71 An erroneous insertion prevention member 74 which moves to a retracted position where the second optical connector 52 is insertable into the second insertion ports 72 and 77 in conjunction with the insertion of the first optical connector 51 into the first and second optical connectors 72 and 76, And an abutting member 78 which comes into contact with the erroneous insertion prevention member 74 when the first optical connector 51 is inserted into the insertion openings 72 and 77 of the first optical connector 2.内視鏡装置1は、内視鏡コネクタ20と、プラグ部41から延設された第1の光コネクタ51と、第1の光コネクタ51が挿入されるレセプタクル部31の第1の挿入口71,76と、第2の光コネクタ52が挿入されるレセプタクル部31の第2の挿入口72,77と、第2の挿入口72,77に一部が配設され、第1の挿入口71,76への第1の光コネクタ51の挿入に連動して、第2の光コネクタ52が第2の挿入口72,77に挿入可能となる退避位置に移動する誤挿入防止部材74と、第2の挿入口72,77への第1の光コネクタ51の挿入時に、誤挿入防止部材74に当接する当接部材78と、を具備する。
