The paper built 2D model by using finite volume method (FVM) to analyze the effect of water intrusion and recession on levee-breach flood routine in flood protected zone quantitatively.It solved the space discretization and time discretization of calculation region by second-order TVD format and second-order Runge-Kutta method,and quantitatively analyzed the influence of water intrusion and recession on levee-breach flood routine and immerse scope in flood protected zone.The calculated submerged scope of the model is verified.The results show that when the levee-breach width increase 50 meters the flood storage quantity of flood protected zone decreases 8 percent. With the increase of breach width, the water level rises, but the maximum water depth does not change significantly with change of time.The change rate of submerged area is less,and the largest submerged area differs by 1.8%. The effect of water intrusion and recession is very obvious,the difference between the maximum flood volume and maximum submerged area is more than 60%.Water intrusion and recession will cause greater flood losses compared with the increase of levee-breach width in flood protected zone.