The Laot Customary Law Institution, led by a Panglima Laot, is a traditional institution that regulates the use and management of coastal and marine resources. This institution is responsible for implementing and supervising customary rules in the maritime sector which have been established and decided through customary deliberations of the sea handlers living in the area. The Aceh Sea area has many natural marine resources, both biological and non-natural, which makes it prone to illegal fishing. In addition, the Panglima Laot regulations state that fishermen are prohibited from bombing, poisoning, anesthetizing, electrifying, harvesting coral reefs, and other actions that could damage habitats and other biota. This research aims to analyze and study in depth the supervision of Panglima Laot Lhok in preventing illegal fishing. Primary and secondary data are the data sources used in the descriptive qualitative method. The research uses data obtained through interviews, observation, and documentation. Based on the results of research and findings in the field, the conclusion is that Panglima Laot Lhok always carries out supervision in preventing illegal fishing, either directly by Panglima Laot Lhok or by coordinating with fishermen who are at sea, however, the very large sea factor means that supervision does not occur properly and thoroughly, and sometimes illegal fishing occurs.
Keywords: supervision, panglima laot lhok, illegal fishing