Abstract: A treatment instrument for an endoscope includes: a front end hood that is provided to a distal end of an inserting portion of the endoscope; a supporting member that is provided inside the front end hood; a treatment member that is rotatably supported by the supporting member; and an operating wire that is coupled to the treatment member and extended rearwardly from the front end hood. The treatment member is rotated about the supporting member by operating to extract and retract the operating wire at a base side of the endoscope.