A control system having improved maintainability and operability is provided. To this end, in a control system comprising a plurality of field devices distributed in equipment and a controlling input/output device, and a host controller connected to the plurality of field devices via a transmission line and controlling the field devices, the field devices and the host controller constituting a network in the equipment for control of the equipment, the control system further comprises a plurality of connectors for connecting the plurality of field devices to the transmission line, the connectors having network IDs representing respective connected positions to the network, and a node address creating unit for generating node addresses based on the network IDs.