The model-free adaptive control method is applied to the water supply system pressure regulating and flow control. The design of the system controller does not depend on the specific mathematical model, it is directly based on the pseudo-partial-derivative vector; Through a parameter estimation algorithm and according to the correlation information in the water supply system, the pseudo-partial-derivative is on-line derived; The simulation and analysis with Matlab software verifies that the control method can improve the sensitivity and stability of the automatic water supply system and enable the whole system fast to achieve the work steady state.