A distributed control system includes a plurality of controllers each composed of a plurality of processors and being coupled through a network. Each controller includes a scheduler for measuring a load; internal backup means for controlling which controller bears the load; backup request means for requesting another controller to bear the load; and backup accept means for answering to a request for bearing the load from another controller in accordance with the load of the requesting controller. Thus, the load which cannot be executed by one controller can be distributed and executed by other controllers in accordance with their loads.