The endoscope system includes an elongated insertion portion, a flexible tube portion provided on a proximal end side of the insertion portion, and the flexible tube portion provided in the flexible tube portion by an operation on a hand side. An endoscope provided with a hardness changing mechanism for changing the hardness of the endoscope, and an overtube formed in a cylindrical shape having flexibility and extending in the axial direction into which the insertion portion is inserted. In the mirror system, the hardness change region of the flexible tube portion by the hardness change mechanism portion is set so as to reach from the middle portion to the base end portion of the flexible tube portion, and the total axial length of the overtube Was set shorter than the total length of the hardness change region.内視鏡システムは、細長に形成された挿入部と、前記挿入部の基端側に設けられた可撓管部と、前記可撓管部内に設けられ手元側の操作により前記可撓管部の硬度を変更する硬度変更機構部とを備えた内視鏡と、前記挿入部が挿入される、可撓性を備え軸方向に延びる筒状に形成されたオーバーチューブと、を備えた内視鏡システムであって、前記硬度変更機構部による前記可撓管部の硬度変更領域を、前記可撓管部の中途部分から基端部に至るよう設定すると共に、前記オーバーチューブにおける軸方向の全長を、前記硬度変更領域の全長より短く設定した。
