This paper assesses the performance of a floating breakwater with additional wave energy conversion function.According to volume of fluid(VOF)method and finite element spatial discrete method,we establish a two-dimensional numerical wave flume,further study the simulation of wave-double floating bodies interaction based on the study of single float’s hydrodynamic performance,record the wave elevations front and rear of the floating body,and research the influences of the damping coefficient applied on it to the wave transmission coefficient and wave power extraction efficiency.The results show that the damping coefficient has a greater influence on the transmission coefficient and energy extraction efficiency of the double-floating system than that of the single-floating system,so double-floating system is more sensitive to variation of damping coefficient than the single-floating system.Under the same wave condition,the energy extraction efficiency of the double cylindrical float is not simply 2 times higher than that of the single cylindrical float.The ratio of the two is always greater than 2 in the scope of the study,which indicates that the interaction between the floats is positive and conducive to energy extraction.