T The numerical investigation of regular waves interacting with a submerged horizontal twin-plate breakwater is pre-sented in this paper. A numerical model with an absorbing wave-maker is established based on the VOF method. The va-lidity of the model is verified by experimental results. Comparisons between the numerical and experimental results show that both the water surface profiles and the wave-induced pressures can be modeled accurately. Wave deformation over the breakwater, water particle, velocities around the breakwater, and the wave-induced pressures on the structure are nu-merically investigated. The pressure amplitudes of the fimdamental and second harmonics on the model surface are exam-ined in various water depths. The computed and experimental results have revealed that the higher frequency components are, generated at the onshore side of the breakwater. Furthermore, the computed results demonstrate a circulating flow formed at the onshore side of the breakwater.