Provided are a treatment tool, an endoscope device, an endoscope system, and a treatment method that lift the treatment site and lift the lesion site so as to expose the site to be treated and make it easily visible, whereby other treatments of the treatment site can be performed safely, reliably and easily. An endoscope treatment tool 20 comprises an insertion portion 21 which can be inserted into a first treatment tool channel 14 of an endoscope 2 of an endoscope system 1； an operation unit 22； and an operation wire 27 that is pulled by the operation of the operation unit 22, wherein the insertion portion 21 includes a distal end portion 23 having a grip portion 24 that can be opened and closed, a bendable bending portion 25, and a connection portion 26 that connects the bending portion 25 and the operation unit 22； the connection portion 26 is advanced and retracted along the longitudinal axis of the connection portion 26 and rotated about the longitudinal axis by the operation of the operation unit 22； the grip portion 24 is advanced, retracted or rotated when the connection portion 26 is advanced, retracted or rotated； the grip portion 24 is closed when the operation wire 27 is pulled； and the bending portion 25 is bent in a state where the grip portion 24 is closed.L'invention concerne un outil de traitement, un dispositif d'endoscope, un système d'endoscope et un procédé de traitement qui soulèvent le site de traitement et soulèvent le site de lésion de façon à exposer le site à traiter et le rendre facilement visible, ce qui permet d'effectuer d'autres traitements du site de traitement de manière sûre, fiable et facile. Un outil de traitement d'endoscope 20 comprend une partie insertion 21 qui peut être insérée dans un premier canal d'outil de traitement 14 d'un endoscope 2 d'un système d'endoscope 1 ； une unité d'actionnement 22 ； et un fil d'actionnement 27 qui est tiré par le fonctionnement de l'unité d'actionnement 22, la partie insertion 21 comprenant u
