Abstract: The integrated system of floating breakwater and wave energy device has a dual function of wave energy utilization and wave attenuation. The numerical simulation of the hydrodynamic wave interaction with integrated system has practical significance. Using the two-dimensional finite difference simulator for incompressible fluid based on the high-order constrained interpolation CIP (Constrained Interpolation Profile) method, the hydrodynamic and energy output characteristics of the integrated system with wing plates of different lengths under different wave conditions are investigated. The flow field and vorticity during the hydrodynamic wave interaction with the integrated system were analyzed. The calculation results show that the proposed numerical model can effectively simulate strong nonlinear phenomena such as wave breaking. Installing wing plates can reduce the wave transmission coefficient and significantly improve the maximum wave energy capture width ratio of the system. When the length of the wing plates increase, the wave energy capture width ratio of the system gradually increases and finally reaches a steady state.