Abstract: The systematic architecture of the on-site bus control system and the control process of the rolling parameters of PQF mandrel pipe mill are described based on the application of PROFIBUS on-site bussing technique in a large sized pipe rolling plant in China, from which the key technical points of how to build a stacked type PROFIBUS-DP bus network structure are summed up. With the use of the on-site bus control system, the information isolated island is eliminated among the quality assurance system QAS, analog computing system PSS, hydraulic roll gap control system of mandrel rolling mill HCCS and automatic control system BAS, through which Information resources sharing is realized so that the productivity is increased and the Product quality accident cost and production failure cost are reduced.