An instrument (1 61 101 201 301 301a 500 600) for an endoscope includes a first insertion portion (10 71 120 206 313) having an base end to which an operation section is connected a first offset portion (11 72 130, 135 205c 312, 320) extending outward from an axis of the first insertion portion a second insertion portion (12 73 140, 145 205d 325) having a base end joined to the first offset portion and an element extending parallel to the axis of the first insertion portion a second offset portion (14 74 155, 160 205e 330, 341) which is joined to a head of the second insertion portion and reaches an extension of the axis of the first insertion portion and a third insertion portion (16 75 165 209 343) which is joined to the second offset portion and has a portion arranged on an axis which is substantially the same as at least a part of the axis of the first insertion portion. An inner hole is formed through the first insertion portion, the first offset portion, the second insertion portion, the second offset portion, and the third insertion portion.