Under the circumstances of pure lag in feedback control system and the imprecision of the controlled object model, the fuzzy logic and pure lag compensation theory is used to design a Fuzzy PI-Smith control system . By the Simulink toolbox and Fuzzy logic toolbox of MATLAB, the system has been simulated. The simulation results show that the Fuzzy PI-Smith system has faster response speed and smaller overshoot than the traditional PI-Smith system.The explicit formulation of Fuzzy PI-Smith system is derived, and it lay the basis for the practical application of control algorithms.