PROBLEM TO BE SOLVED: To provide a manufacturing method of a treatment instrument for an endoscope and a treatment instrument for an endoscope manufactured by the same, which can bond an operation wire and a wire treatment instrument having a large outer diameter difference without incurring variations in bonding strength and reduction in product performance, and in addition, can greatly shorten a hard part length as compared with the conventional treatment instrument.SOLUTION: A treatment instrument 1 for an endoscope comprises: a metal operation wire 22； a snare 23 formed by bundling ends of metal wires； and a connection part 24 which is formed by twisting a plurality of metal wires constituting a base end part 234 of the snare 23 and has an outer diameter equal to the outer diameter of the operation wire 22. An end face of the operation wire 22 and an end face of the connection part 24 are joined together by upset resistance welding in a state of abutting each other.SELECTED DRAWING: Figure 3【課題】接合強度のばらつきや製品性能の低下を招くことなく、外径差の大きい操作ワイヤおよびワイヤ処置具を接合することができ、加えて従来よりも硬質部長を大幅に短縮することができる内視鏡用処置具の製造方法およびそれにより製造された内視鏡用処置具を提供すること。【解決手段】内視鏡用処置具１は、金属製の操作ワイヤ２２と、金属ワイヤの端部を束ねて形成されたスネア２３と、スネア２３の基端部２３４を構成する複数の金属ワイヤが撚り込まれることにより形成され、操作ワイヤ２２の外径と等しい外径を有する連結部２４と、を備え、操作ワイヤ２２の端面と連結部２４の端面とは、互いに突き合わされた状態で、アップセット抵抗溶接により接合されている。【選択図】図３
