Abstract: To the control problems in the biology processing system of integrated oxidation ditch, the DCS system practical scheme that consists of practical, field bus based ADAM-5000/CAN series and IPC is presented to sewage treatment at some factory. The scheme that adoptes ADAM-5000/CAN in the field has the characteristics of multi-master structure, real-time capability and high reliability communication. Besides the IPC that integrates monitor with control has rich resource, thus the DCS system possesses reliable open system architecture, quality real-time capability, high reliability and expedient operability.