Abstract: Taking use of digitizing technique,this paper discusses how to develop a canal automatic control system,combining with theories of Hydraulics,Fuzzy control,set up the mathematics mould of canal automatic moving system,design a fuzzy control system,present its fuzzy rules and membership functions etc,so that the system is more stable and more rational.At last,the system actual parameters are simulated in MATLAB,providing important data and basis for making decision and canal system moving automatically.