Fishing ports are associated with environmental issues such as waste disposal into waters and land, air pollution, and noise. One effort to minimize polluted waste is the existence of a Waste Water Treatment Plant. Wastewater Treatment Plants are one of the functional facilities at fishing ports based on the Minister of Maritime Affairs and Fisheries Regulation No. 08/MEN/2012 Concerning Fisheries Ports. This research aims to identify liquid waste management at the Belawan Ocean Fishing Port, analyze the quality of liquid waste from fishing activities at the Belawan Ocean Fishing Port, analyze the capacity planning of the Waste Water Treatment Plant and stakeholder interaction patterns in waste handling, and develop a liquid waste management strategy at the Belawan OFP. The study conducted a direct survey in Belawan by interviewing the community, fishermen, and Belawan OFP staff and taking water samples for water quality data tested in the laboratory. The research results show that water pollution in the Belawan OFP comes from industry, residential areas, fisheries, and transportation. Laboratory analysis indicates that Total Suspended Solids and ammonia exceed quality standards caused by residential waste and the disposal of dead fish. The strategy for developing liquid waste management at Belawan OFP directs economic aspects as the main priority.