The process of overtopping breach and the numerical simulation of coastal flood evolution in urban interior at home and abroad was summarized. The mechanism model of dike-break was reviewed from three aspects, including the erosion at the bottom of the breach, the widening of the side wall of the breach and the retrogressive erosion of the downstream slope. The advantages, disadvantages and applicability of various flood inundation models and the generalization method of urban buildings were analyzed. Aiming at the shortcomings in the current study, it is necessary to improve the flood model of seawall breaching through physical model tests, strengthen the research of erosion and transportation of sediment in the breach, improve the theory of sediment transport in high-speed flow, optimize the porosity model of urban flood, and fully consider the impact of urban drainage system and vehicles on flood propagation.