Aiming at the problems of low control accuracy and low reliability of the traditional material mixing device, this paper proposes to use Siemens S7-1200 PLC and touch screen to control and monitor the working process of the material mixing system, so as to realize the control functions of the two materials from feeding, stirring to discharging. Control unit based on TIA Botu fully integrated automation software platform to compile ladder diagram. Touch screen as a function of PC to realize man-machine interface interaction, the test shows that using modular programming software instead of traditional relay control, the control valve to realize opening and closing function accurately, liquid level fluctuation simulation process is true, accurate, the system runs stably, not only can greatly improve the production efficiency, and can reduce the failure rate.