To solve the problems of the backward and aging systems in FOCKE350S electric control and monitoring, Siemens S7-300 series CPU is adopted with its original control logic for upgrading while the high performance industrial computer and the C# language are used, with PLC communicating through OPC protocol, a set of new monitoring system is established. Measured operating results show that the upgraded electronic control system is stable with easy maintenance, easy expansion, and the design requirement is met in every aspect.