A production management system controls a production line having a plurality of assembling/machining stations including pieces of production equipment such as nut runners. The production management system includes a computer for supplying control information to control the pieces of production equipment, a first information network for transmitting the control information from the computer to the assembling/machining stations, and a second information network for transmitting information indicating results of operation in the assembling/machining stations to downstream assembling/machining stations to allow defective portions of workpieces to be repaired in the subsequent assembling/machining stations. The first information network comprises a plurality of separate networks associated respectively with divided portions of the production line.
