High-frequency treatment tool

A high-frequency treatment tool comprising:

• an operating wire having a treatment part including a treatment electrode;
• a first tube formed from an insulating material, in which the operating wire for enabling the treatment part to protrude and recede is inserted;
• and
• a second tube having a passive electrode with a distal-end face at a distal end, in which the first tube is inserted so as to cover an inner peripheral face of the passive electrode;
• wherein a large-diameter part formed in a distal-end part of the first tube contacts the distal-end face of the passive electrode;
• the passive electrode includes a through-hole extending in the axial direction of the passive electrode;
• an outer diameter of the large-diameter part is larger than an inner diameter of the through-hole;
• and
• a retraction of the distal-end part of the first tube into the through-hole is restricted by an engagement of the large-diameter part and the distal-end face of the second tube.