To realize torque control based on an estimated external force and to cope with more various situations. Provided is a medical support arm system including: a support arm that is a multilink structure having a plurality of links connected by a joint unit including an actuator, and configured to support a medical unit; and a control device including an external force estimation unit configured to estimate an external force acting on the joint unit on the basis of a drive characteristic of the actuator, and a joint control unit configured to control drive of the joint unit on the basis of an external torque estimated by the external force estimation unit.