A method for controlling a surgical robot includes calculating an external force acting on a robot arm mounted with a surgical instrument, filtering the external force acting on the robot arm when a central point of an incision is set, calculating a virtual force to enable the surgical instrument which is positioned away from the central point of the incision to return to the central point of the incision, and applying the calculated virtual force to the filtered external force, to control movement of the robot arm. As a result, it is possible to compactly design the surgical robot and thereby reduce the volume of the surgical robot.