And wherein the endoscope device (1, 70), the treatment instrument main body (24), distal end treatment unit provided in the distal direction side of the treatment instrument main body (24) and (26), the distal end treatment portion (26) treatment instrument comprising rotating joint that rotates about the axis with respect to the treatment instrument main body (24) and (27) and (20,50,55,60,70), wherein the endoscope or endoscope (2) The tubular body is provided in another body (71) and the mirror (2), in defining a (18) biopsy channel inserted through the therapeutic device (20,50,55,60,70) peripheral surface ( I comprise, and 17,73). The endoscope device (1, 70), when the treatment instrument main body (24) rotates about the axis of the endoscope (2), the inner peripheral surface of the (17,73) I comprises (41, 51, 61) the frictional force applying part for imparting a frictional force to the contact portion between the outer peripheral surface of the portion of the distal end direction of the treatment instrument main body (24) and part of the distal end direction.内視鏡装置(1,70)は、処置具本体(24)と、前記処置具本体(24)より先端方向側に設けられる先端処置部(26)と、前記先端処置部(26)を前記処置具本体(24)に対して軸回り方向に回転させる回転関節部(27)とを備える処置具(20,50,55,60,70)と、前記内視鏡(2)又は前記内視鏡(2)とは別体の管状体(71)に設けられ、前記処置具(20,50,55,60,70)が挿通される処置具挿通路(18)を規定する内周面部(17,73)と、を備える。また、内視鏡装置(1,70)は、前記処置具本体(24)が前記内視鏡(2)に対して軸回り方向に回転する際に、前記内周面部(17,73)の先端方向側の部位と前記処置具本体(24)の先端方向側の部位の外周面との接触部に摩擦力を付与する摩擦力付与部(41,51,61)を備える。
