Sewage treatment unit adopt living beings is it oxidize law and materialization treatment disinfect principle punish the sanitary sewage of boat to exposed to. The structure form and performance of this device meet the demand for national standard GB10833-89 " technological terms of sewage disposal system of ship life ", the device is small, heavy and light, the structure is compact, the treated discharge water accords with the discharge standard of the national regulation, meet the discharge standard demand of knowing IMO MEPC/2 (VI ) of international Taiwan Strait Exchange Association's environmental protection at the same time. Device this made up of five chambers, crush room, two living beings is it oxidize the room, precipitate the room and disinfection room to contact.