To provide an operation device for a medical treatment tool capable of improving operation ability.SOLUTION: An operation device 30 for a medical treatment tool is arranged in a proximal end of a catheter part 10 of a medical treatment tool comprising: the catheter part 10 having a tube 12 into which an operation wire 11 is slidably inserted； and a processing part 20 arranged on a distal end of the catheter part 10. The operation device comprises: a base member 31 to which the tube 12 is connected, and which has a rail part 31c in an almost linear state； and a slider member 32 to which the operation wire 11 is connected, and which is slidably attached to the base member 31 along the rail part 31c. The base member 31 has a first finger hook part 31a on a position closer to a proximal end side than to the slider member 32, and has a second finger hook part 31b on a position closer to a distal end side than to the slider member 32, and the slider member 32 has third and fourth finger hook parts 32a, 32b.SELECTED DRAWING: Figure 1【課題】操作性を向上することができる医療用処置器具の操作装置を提供すること。【解決手段】操作ワイヤ１１がスライド可能に挿通されたチューブ１２を有するカテーテル部１０と、カテーテル部１０の遠位端に配置される処置部２０とを備える医療用処置器具のカテーテル部１０の近位端に配置される操作装置３０である。チューブ１２が接続され、略直線状のレール部３１ｃを有するベース部材３１と、操作ワイヤ１１が接続され、レール部３１ｃに沿ってスライド可能にベース部材３１に取り付けられたスライダ部材３２とを備える。ベース部材３１は、スライダ部材３２よりも近位端側に第１指掛部３１ａを有し、スライダ部材３２よりも遠位端側に第２指掛部３１ｂを有し、スライダ部材３２は、第３指掛部３２ａおよび第４指掛部３２ｂを有する。【選択図】図１
