A high-frequency treatment tool (1) includes an operating wire (12) having a treatment part (10) including a treatment electrode a first tube (23) formed from an insulating material, in which the operating wire (12) for enabling the treatment part (10) to protrude and recede is inserted and a second tube (21) having a passive electrode (22) at a distal end, in which inserted the first tube (23) such as to cover an inner peripheral face of the passive electrode (22) is inserted. An engagement part (25) and an engaged part (22C) that can engage with each other are formed in the first tube (23) and the passive electrode (22), and the engagement of the engagement part (25) with the engaged part (22C) restricts the relative movement of a distal-end part of the first tube (23) to a proximal-end side of the first tube (23) with respect to the passive electrode (22).
