A medical apparatus has a first device, a second device, a connection signal output portion and a main body apparatus. The first device includes a grasping portion, a probe connected to the grasping portion and capable of transmitting at least one of an ultrasound vibration and a high-frequency current, and a treatment portion provided at a distal end portion of the probe and for transmitting at least one of the ultrasound vibration and the high-frequency current transmitted by the probe, to living tissue. A second device includes a jaw member for holding living tissue between the treatment portion and the jaw member, a movable handle for holding the living tissue by moving the jaw member toward the treatment portion, and a recessed portion for being attachably and detachably engaged with the first device. The connection signal output portion outputs a connection signal indicating that the first device is connected to the recessed portion of the second device. The main body apparatus controls output of a drive signal for supplying at least one of an ultrasound vibration and a high-frequency current to the first device.
