The present invention is a light source cooling method of ballast water treatment apparatus using the ultraviolet light-emitting diodes, and relates to a ballast water treatment apparatus using the foregoing method, specifically, the inlet inner surface side and the outlet side of the pipe portion formed in the front of the housing than on, but the inlet end are installed, respectively, bent formed cooling water outlet pipe cooling water inlet pipe and the outlet end is formed bent toward the inlet side of the inlet tube facing the outlet side of the inlet pipe, the cooling water inlet pipe is inside the heat sink of the light source the through-connection on the inlet side of the flow path formed in said cooling water outflow pipe of the coolant inlet pipe when the connection to the outlet side of the flow path is through-formed in the heat sink of the light source to the number of ballast water into the inlet pipe portion of the housing inlet the inlet end and so as to natural circulation to cool the light source through the cooling water outlet pipe passage and the cooling water outlet pipe being by a pressure difference generated between the outlet end through forms a part of the ballast water in the interior of the heat sink of the cooling water inlet pipe and the light source of the configured by, reduced efficiency degradation caused due to heat generation of the separate makes it possible to efficiently cool the ultraviolet light-emitting diode constituting the light source unit by using the natural cycle of the ballast according to the pressure difference, without power consumption ultraviolet light-emitting diode and life able to solve the problem completely because it would allow one to further accelerate the commercialization of a ballast water treatment apparatus using an ultraviolet light-emitting diode.본 발명은 자외선 발광다이오드를 이용한 선박 평형수 처리장치의 광원부 냉각방법 및 그 방법을 이용한 선박 평형수 처리장치에 관한 것으로, 보다 상세하게는 하우징의 전방에 형성된 유입관부의 입구측과 출구측 내측면에 유입단부가 유입관부의 입구측을 향하도록 절곡형성된 냉각수유
