Abstract: Suitability assessment is the foundation and precondition of ecological seawall construction. In view of the lack of index system and method of suitability assessment for ecological seawall construction, analytic hierarchy process is used to establish an index system evaluated from two aspects, the disaster prevention capability of seawall and the eco-environment of the seawall, by principles of systematicness, representation and operability. Index weight and quantitative criteria are established by combining with the Delphi method. The indexes of disaster prevention capability of seawall and ecological environment around seawall are introduced and divided. And the suitability of ecological seawall construction is divided into prioritized construction, moderate construction and maintaining the current status according to mutually exclusive matrix of defense and ecology. Finally, the index system is applied to Yufan Seawall on Pingtan Island for evaluations of disaster prevention capability and seawall ecosystem. The results show that it is the type of prioritized construction because its disaster prevention capability is poor with general ecological environment. The index system can thus be taken to evaluate the suitability of ecological seawall construction.