TREATMENT TOOL

A treatment tool includes: a pair of openable/closable jaws; a substrate provided on at least one of the jaws; a wiring pattern provided on one surface of the substrate in a state of being electrically insulated from the substrate, the wiring pattern including an electric resistance pattern configured to generate heat when a current is carried to the electric resistance pattern, and a connecting section configured to be electrically continuous to the electric resistance pattern; and a heat transfer plate disposed facing the one surface and configured to transfer, to a living tissue, the heat in contact with the living tissue; and a lead wire configured to be a current-carrying path to the wiring pattern, the lead wire being positioned on a side separated from the heat transfer plate with respect to the wiring pattern and being electrically connected to the connecting section from the separated side.