Abstract: The wave pressure and the structural response under wave impact were studied using the multi-material ALE (Arbitrary Lagrangian-Eulerian) method. Firstly, a breakwater-wave coupling model based on the physical model was constructed. Meanwhile, the model and approaches were validated by comparison with wave theory and experimental data. Secondly, both straight and curved breakwater-wave coupling models were constructed. The influences of the structure response, the section size and the shape of breakwater axis on the wave impact were analyzed. The results showed that the maximum wave pressure on the front and rear seawall generally appear at the static water level and the bottom of rear wall, respectively. The front wall and breakwater width have a protective effect on the rear wall. Because of the structural response effect, the pressures on the front seawall are increased while the pressures at the rear seawall are decreased. Both the wave pressure and structural stress show peaks in the curved segment of the overall model.