This system is provided with a converter (4) for converting alternating current to direct current, an inverter (5) for converting the direct-current power supplied from the converter (4) to alternating-current power, a servo control device (13) for controlling the driving of servomotors (8), and a resistance regenerating circuit (10) for consuming regenerated energy. The servo control device (13) has a plurality of motor control units (14) capable of controlling the plurality of servomotors (8), and a plurality of control port units (15) corresponding to the plurality of motor control units (14). At least one of the plurality of motor control units (14) is configured to be able to switch between a power source regeneration control function unit (16) for controlling a power source regenerating circuit, and a unit (17) for controlling the functioning of the servomotors (8). It is possible to provide a robot control system that keeps development costs from increasing and enables a power source regeneration function to be added.