A treatment instrument (1) for endoscope includes: a pair of forceps members (first forceps member (11) and second forceps member (12)) being supported by a forceps rotation axis (13) so as to be capable of rotating relative to each other an operation part configured to open and close the pair of forceps member an operation wire (31) connecting the pair of forceps members with the operation part a connection member (34) being provided on a distal end of the operation wire, the connection member including two link rotation axes (34A, 34B) having axis lines disposed in parallel to each other and separating from an axis line of the operation wire and a pair of link members (first link member (35) and second link member (36)), first ends thereof being connected with proximal ends of each of the pair of forceps member so as to be capable of rotating, second ends thereof being connected with each of the two link rotation axis so as to be capable of rotating, wherein the pair of link member are parallel in the state where the pair of forceps member are closed.
