To solve the problem of stochastic uncertainty problem of seawall structure safety，we analyze the influence factors such as wave，tide，and wind on the role of the seawall structure based on the Monte-Carlo method of structural reliability analysis theory，and establish the safety of the seawall structure under multiple failure modes analysis of functions and the analysis method according to the characteristics of the seawall structure in our country. Based on the reliability analysis of a typical seawall structure with the established multiple failure modes，we obtain the failure probability of seawall structure under various failure modes and analyze the relationship between the sensitivity of main influencing factors and failure probability. The results show that the method can be applied to the safety assessment of the existing seawall and the safety design of the newly built or planned seawall.