Provided is a treatment tool configured so that no induction current flows through a manipulation wire of a manipulation part manipulated by an operator. The treatment tool includes: the manipulation part that is manipulated by an operator； an elongated insertion portion that is elongated from the manipulation part and is inserted into a body of a subject； and the manipulation wire that passes through the elongated insertion portion to transmit manipulation at the manipulation part to a treatment portion on a forward-end side (distal-end) of the insertion part. The manipulation wire includes a first wire having one end connected to the treatment portion, to which AC magnetic field or AC electrical field is applied, and a second wire having one end connected to the manipulation part and the other end that is connected to the first wire but is insulated electrically from the first wire.
