To decrease the costs associated with wave energy conversion and improve the performance of wave energy converters (WECs), a multi-float WEC that also serves as a breakwater is proposed, and its hydrodynamic performance is explored through physical model tests. The control variable method was used to investigate the free water surface, the dynamic response of the floats, and the energy conversion of the device under different PTO damping loads and wave conditions. These tests allowed for an analysis of the wave energy capture, as well as the device’s ability to prevent and dissipate waves. The test results show that the device functions well as a breakwater, with an average transmittance of 0.48 under typical test conditions, meaning that less than a quarter of the wave energy is transmitted to the rear of the device. Moreover, the device can effectively convert wave energy, with K_e exceeding 20% within the range of 0.64≤kh≤1.39 under suitable PTO loads.