The purpose of the present invention is to change a discharge angle of a fluid with a simple manipulation. Provided is a high-frequency medical instrument (1), comprising: a long and narrow cylindrical sheath (2) which is inserted within a body an electrode member (3) which is positioned within the sheath (2) to be movable in the longitudinal axis direction, and whereto high-frequency current is supplied and a fluid conveyance means which is connected to the base end side of the sheath (2), and which conveys a fluid via a flow path (9) which is formed in the longitudinal axis direction of the sheath (2). Disposed in the leading end of the sheath (2) are a sliding hole (6a) in which the electrode member (3) is inserted and positioned to be movable, and a discharge aperture (9a) which discharges a fluid (C) which is conveyed by the fluid conveyance means. Disposed in the leading end of the electrode member (3) is a leading end part (3b) which is bigger than the sliding hole (6a) and extends radially outward in a flange shape. The discharge aperture (9a) is formed in a shape and location which changes the discharge angle with respect to the longitudinal axis of the fluid (C) which is discharged forward, according to the distance of the leading end part (3b) from the leading end of the sheath (2).Lobjectif de la présente invention est de modifier un angle de décharge dun fluide avec une simple manipulation. Linvention concerne un instrument médical haute fréquence (1), comprenant : une gaine cylindrique, longue et étroite (2) qui est insérée à lintérieur dun corps un élément délectrode (3) qui est positionné à lintérieur de la gaine (2) pour être mobile dans la direction de laxe longitudinal, et auquel un courant haute fréquence est fourni et un moyen de transport de fluide qui est relié au côté extrémité de base de la gaine (2), et qui transporte un fluide par lintermédiaire dune voie découlement (9) qui est formée dans la direction de laxe longitudinal de la gaine (
