A medical treatment device 1 comprising: a vibration section 8 that is provided with first and second ultrasonic vibrators 81 and 82 a probe 6 that linearly extends and transmits ultrasonic vibrations generated respectively by the first and second ultrasonic vibrators 81 and 82 from one end to the other end a jaw section 9 that enables holding of a biological tissue together with the other end of the probe 6 and is rotatable around the central axis of the probe 6 a rotary angle detection section that detects the rotary angle of the jaw section 9 an output calculating section that calculates outputs, whereby the first and second ultrasonic vibrators 81 and 82 are respectively driven, on the basis of the rotary angle of the jaw section 9 and a vibration-driving section that is electrically connected to each of the first and second ultrasonic vibrators 81 and 82 and drives the first and second ultrasonic vibrators 81 and 82 respectively by the outputs calculated by the output calculating section. The aforesaid outputs set up the direction of the vibration of the other end of the probe 6 looking from the direction along the central axis, said vibration being caused by the ultrasonic vibrations of the first and second ultrasonic vibrators 81 and 82, in the direction from the central axis toward the jaw section 9.Linvention concerne un dispositif de traitement médical 1 qui comporte : une section de vibration 8, qui est pourvue de premier et second vibrateurs ultrasonores 81 et 82 une sonde 6, qui sétend de façon linéaire et qui transmet des vibrations ultrasonores générées respectivement par les premier et second vibrateurs ultrasonores 81 et 82 dune première extrémité à lautre extrémité une section de mâchoire 9, qui permet de tenir un tissu biologique conjointement avec lautre extrémité de la sonde 6 et qui peut tourner autour de laxe central de la sonde 6 une section de détection dangle de rotation, qui détecte langle de rotation de la section de mâchoire 9 une se
