An endoscopic high-frequency treatment tool includes an insulating flexible sheath a conductive stranded wire made of metal and a cover sheath which is fitted on a portion of the conductive stranded wire in the vicinity of a end thereof. The conductive stranded wire is inserted into the insulating flexible sheath so as to be rotatable about an axis of the conductive stranded wire from a proximal end side thereof, and a part of wire strands of the conductive stranded wire is extended outwards from a portion of the insulating flexible sheath in the vicinity of a end thereof to be used as a high-frequency cutting electrode.
