Abstract: Applying modern control principles and bond graphic modeling theory, a mathematical model on the dynamic operation mode of auto-delay valve has been built in state equations. The digital simulation results, which are concluded through adopting Hidden Behind-Eula method, prove that the valve has better dynamic performances under different working pressure. Applying complex-optimization, the main parameters have been optimized. Conclusions show that the valve's design is rational, its performances are good and the delaying effect is obvious.