Abstract: According to the situation in Zhaolou coal preparation plant,presents a fuzzy control method controlling multi-process parameters.In this method two separate fuzzy controllers are used for controlling density and liquid level,and the magnetic content as the regulatory factor participate the control of density and liquid level,finally the three parameters above reached balance that ensured steady characteristics of suspension.According to the production data of trial run,the method is effective and simple and satisfied the requirements of production control.