For the purpose of switching the liquid feeding state according to the open / close state of the forceps, the endoscope treatment tool (1) according to the present invention has a conduit (2a) capable of feeding liquid, and is provided in the channel of the endoscope. A forceps part (3) provided with a pair of forceps pieces (3a) disposed in a projecting state from a distal end cover (30) provided at the distal end of the sheath (2) and capable of opening and closing； An operation member (4d) that is connected to the proximal end of the forceps part (3), opens the forceps piece (3a) by advancing in the longitudinal direction, and closes the forceps piece (3a) by retreating, and a through-hole that penetrates the operation member (4d) (7a), the first liquid feeding hole (9) is constituted by the gap between the through hole (7a) and the operating member (4d), and the second gap is formed by the gap between the inner peripheral surface of the tip cover (30). And a flow path forming member (7) that constitutes the liquid feeding hole (8), and the operation member (4d) It hits the flow path forming member (7) when d) have been advanced, the large-diameter portion is provided for closing the first liquid feed hole (9). 鉗子の開閉状態に応じて送液状態を切り替えることを目的として、本発明に係る内視鏡処置具（１）は、送液可能な管路（２ａ）を有し、内視鏡のチャネル内に挿入可能なシース（２）と、シース（２）先端に設けられた先端カバー（３０）より突出状態に配置され、開閉可能な一対の鉗子片（３ａ）を備える鉗子部（３）と、鉗子部（３）基端に接続され、長手方向の前進により鉗子片（３ａ）を開き、後退により鉗子片（３ａ）を閉じる操作部材（４ｄ）と、操作部材（４ｄ）を貫通させる貫通孔（７ａ）を有し、貫通孔（７ａ）と操作部材（４ｄ）との隙間により第１の送液孔（９）を構成し、先端カバー（３０）の内周面との隙間により第２の送液孔（８）を構成する流路形成部材（７）とを備え、操作部材（４ｄ）に、操作部材（４ｄ）が前進させられたときに流路形成部材（７）に突き当たって、第１の送液孔（９）を閉塞する大径部が設けられている。
