Abstract: Described in the article are the main aspects of the PROFIBUS field bus system, covering the concept, configuration, PROFIBUS-DP protocol, configuration of the network as well as the application of the bus system to the basic automation system of the straightening area auxiliary machine system in the 14" MPM plant of Pangang Group Chengdu Iron & Steel Co., Ltd. Also elaborated are soft/hardware selection, configuration and functions of the above mentioned basic automation control system.