The quadruple-tank system is a typical multi-level system with characteristics such as slow dynamics, strong coupling and nonlinear etc, and can be used to simulate the motion of minimum system or nonminimum system. This paper firstly determine the distributed control structure on the basis of relative gain array (RGA) analysis, then predictive PI control strategy is proposed. Simulation results show that distributed predictive PI control can efficiently overcome control input saturation, considerably enhance dynamic performance and easily apply to engineering, compared with traditional PI control.