The object of the invention is to automatically adjust the angle of an end effector to improve on the operability of medical treatment tools. The medical system of the invention comprises a slave medical treatment tool to be controlled and including a moving joint for adjusting the angle of a first end effector relative to a first shaft a master medical instrument serving as a master control instrument and including a second end effector located at a distal end of a second shaft a sensor that produces a sensor signal including at least an angle of the second end effector and a controller that enables follow-up processing for driving a driver such that the angle of the first end effector follows a follow-up criterion set on the basis of a sensor signal produced out of the sensor.
