The invention discloses a novel breakwater and a design method thereof. The breakwater is arranged between a foreshore and a backshore, and comprises a foundation bed and a breakwater body, wherein a riverside slope protecting surface of the breakwater body comprises a slope-shaped riverside slope protecting surface and more than two arc-shaped riverside slope protecting surfaces which are connected together in sequence; a riprapping dike dam is arranged between the bottom end of the slope-shaped riverside slope protecting surface and the foreshore, and the top end of the slope-shaped riverside slope protecting surface is connected with the arc-shaped riverside slope protecting surfaces through a platform; and two adjacent arc-shaped riverside slope protecting surfaces are connected through a corner of the platform. Therefore, in the invention, as the riverside slope protecting surface is combined by the arc-shaped slope protecting surfaces and the slope-shaped slope protecting surface through the platform, the rise of waves and the wave overtopping rate of a breakwater top are effectively reduced through the wave breaking function of the arc-shaped slope protecting surfaces and the energy dissipating function of the slope-shaped riverside slope protecting surface; compared with the conventional breakwater, the novel breakwater can meet design requirements under the same condition more effectively based on a lower altitude of the breakwater top under the same design condition.