This paper briefly introduced the process parameters， configuration of key sensors and process model set- up system of the 1 800 mm 5-stand tandem cold mill in Tangsteel， and made a deep analysis on the process model setup system from aspects of online mathematical setup models， a new multi-object load distribution optimization method based on cost function and model adaptation for on-line rolling process. The actual application result shows that the process control system has stable operation and high accuracy， and the rolling schedule is reasonable. So， the process control system can meet the requirement of online process control.