For manual control of the boiler temperature system error, low security and control processes and complicated issue, application of computer and MCGS for automatic control of the boiler temperature control precision approach to solve the problem of low and security. The use of engineering software MCGS good man-machine interface, data acquisition capabilities, combined with the convenience of script writing, using the conversion module RS485/232 interface to establish MCGS PC and data communication between the boiler tank. MCGS good use control interface and simulation environment, using scripting language programming, take PID algorithm to achieve precise control of the boiler water tank. The practical result shows that this method is simple and reliable to use, can be widely used in industrial production process of temperature control problem. This system is also on the temperature control system to meet the plant's needs, has a considerable application prospects.