The high-frequency treatment instrument of the present invention restricts the movement of the second wire portion (16 e) with respect to the first wire portion (16 b) in the longitudinal axis direction of the second wire portion (16 e) in the sheath portion (12) With the positioning member (14) in the sheath part (12) and with the folded part (16 d) located near the distal end of the sheath part (12), with the second wire part (16 e) being fixed The loop forming portion (16 c) is extended from the distal end of the sheath portion (12).本発明の高周波処置具は、第一ワイヤ部(16b)に対する第二ワイヤ部(16e)の、シース部(12)内での第二ワイヤ部(16e)の長手軸方向への移動を規制する位置決め部材(14)をシース部(12)内に有し、シース部(12)の遠位端近傍に折り返し部(16d)が位置した状態で、第二ワイヤ部(16e)が固定されたままループ形成部(16c)がシース部(12)の遠位端から繰り出される。
