In　this　paper,　the　3-input　and　2-output　water　supply　system　of　the　controlled　watercurtain　cooling　process　in　the　Steel　Plate　Mill　of　Shougang　Group　(in　Beijing,　China)　is　modeled　with　fuzzy　modeling　method　based　on　compositional　rule　of　inference.　Then,　computer　simulations　are　conducted　using　MATLAB.　The　simulation　results　demonstrate　that　the　obtained　models　can　approximate　the　dynamic　response　of　the　objective　system　very　well.