The floating breakwater has the functions of resisting wave propagation and maintaining stability of water surface, and its layout form will have an impact on the shielding effect and the shielding area. This paper uses the CFD method for numerical calculation based on the self-compiled program. The hydrodynamic performance and wave attenuation performance of floating breakwater with arc layout are mainly studied, and the calculation results of linear layout are compared and analyzed. The results show that the rolling response of linear layout under the action of the cross wave is intense, and there is transverse inclination under the action of the oblique wave. The motion of arc layout is relatively stable under the action of cross wave and oblique wave, and the hydrodynamic performance is better. The wave attenuation performance of arc layout is better than that of linear layout under transverse wave condition, while the wave attenuation performance of arc layout is further improved under the oblique wave, and the wave attenuation performance of linear layout is decreased under the oblique wave. It can be seen that the arc layout has better shielding performance than the linear layout under the oblique wave.