An operating shaft member for connecting the treatment portion for performing treatment for the tissue in the body cavity, an operation portion for operating the treatment portion, and said operation section and the treatment section, the operating shaft member movably and a coil sheath portion which is inserted into, the coil sheath portion, than the first coil sheath and having a first coil sheath wire is spirally wound, compression resistance less than the first coil sheath is arranged between the second coil sheath and the first coil sheath is so as to overlap in the radial direction and coaxial and having a second coil sheath with high rotation following capability, a first end of the second coil sheath end and the second parts are connected in a relatively non-rotatable manner about the axis of itself to the operation section and the treatment section, respectively, at least one of said second end and the first end The endoscopic treatment instrument is relatively movable in the axial direction with respect to the first coil sheath.体腔内組織に対して処置を行うための処置部と、前記処置部を操作するための操作部と、前記処置部と前記操作部とを接続する操作軸部材と、前記操作軸部材が進退可能に挿通されたコイルシース部と、を備え、前記コイルシース部は、素線が螺旋状に巻き回された第1コイルシースと、前記第1コイルシースより低い耐圧縮性を有し、かつ前記第1コイルシースより高い回転追従性を有する第2コイルシースと、を有し、かつ前記第1コイルシースと前記第2コイルシースとが同軸かつ径方向に重畳するように配置されており、前記第2コイルシースの第1の端部及び第2の端部は、それぞれ前記処置部及び前記操作部に対して自身の軸線回りに相対回転不能に接続されており、前記第1の端部及び前記第2の端部の少なくとも一方は、前記第1コイルシースに対して軸線方向に相対移動可能である内視鏡用処置具。
