Endoscope 1 e comprises a plurality of metallic cylindrical members 51,55,59,63 which an internal space is electromagnetically connected electrically conductive to shield formed in the insertion portion 2, the insertion portion 2 and the treatment instrument channel 48 the center O1 is disposed a center O to any one quadrant of an orthogonal coordinate system with the origin and extends from the imaging unit 30, at least within the bending portion 7, the curved portion 7 is bent up and down a plurality of small signal cables 31, 32 and 33 centered on the one of the quadrants with other different quadrants that are divided by one axis Y of an orthogonal coordinate system along the direction O2, O3, O4 is disposed , by providing and it is possible to ensure electromagnetic compatibility with (EMC), it was as the plurality of cables can be reduced in diameter insertion portion efficiently positioned to so as not to buckle the curved portion.電子内視鏡1は、挿入部2に形成される内部空間を電磁的にシールドするよう電気的に導通して接続された複数の金属円筒部材51,55,59,63と、挿入部2の中心Oを原点とした直交座標系のいずれか1つの象限に中心O1が配設される処置具チャンネル48と、撮像ユニット30から延出し、少なくとも湾曲部7内において、湾曲部7が湾曲する上下方向に沿った直交座標系の一方の軸Yで区分けされた前記いずれか1つの象限と異なる他の象限に中心O2,O3,O4が配設される複数の小信号ケーブル31,32,33と、を備えることで、電磁両立性(EMC)を確保すると共に、複数のケーブルを湾曲部内で座屈しないように効率よく配置して挿入部を細径化できるようにした。
