medical treatment tool movement, a sheath, and inserted through the operating member to the sheath, a treatment portion provided at a front end portion of the operating member, provided at the proximal end of the sheath, the operating member in the axial direction and an operation portion for rotating about the axis together to, the operation unit includes a body portion having a body-side finger placing portion which is provided at the proximal end of the sheath, it is movable axially relative to the body portion , the proximal end portion of the operating member is fixed, and a slide part having a slide-side finger hook portion on the distal end side than the body-side finger holder in the axial direction, and the movable state the slide portion is axially movable relative to the main body portion , moving toward the proximal end side of the slide portion relative to the body portion and a restricting portion capable of switching and regulating the state of being regulated, restricted state and movable by moving a part of the regulating portion in the axial direction it is switchable between a state.医療用処置具は、シースと、シースに挿通された操作部材と、操作部材の先端部に設けられた処置部と、シースの基端部に設けられ、操作部材を軸線方向に移動させるとともに軸線周りに回転させるための操作部とを備え、操作部は、シースの基端部に設けられるとともに本体側指掛け部を有する本体部と、本体部に対して軸線方向に移動可能とされ、操作部材の基端部が固定され、軸線方向において本体側指掛け部よりも先端側にスライド側指掛け部を有するスライド部と、本体部に対してスライド部が軸線方向に移動可能な可動状態と、本体部に対してスライド部の基端側への移動が規制された規制状態とを切り替え可能な規制部とを有し、規制部の一部を軸線方向に移動させることで規制状態と可動状態との間で切り替え可能である。
