Rapfish is used as an indicator to assess pelagic fisheries' sustainability in Aceh's northern waters. This study aims to determine the sustainability of pelagic fishing and the factors that mostly influence the sustainability of pelagic fisheries. Surveys and interviews with questionnaires were conducted in collecting data, then analyzed by RAPFISH analysis with five dimensions. The results show that the ecological and economic dimensions are in a quite sustainable category, the social dimension is in a less sustainable category, the technological dimension is in the very sustainable category and the institutional dimension is in the less sustainable category. In addition, there are several indicators that most influence the sustainability of pelagic fisheries with purse seine on the ecological dimensions; (1) the location of fishing grounds; (2) the Fishing season. The economic dimension is influenced by (1) assistance from the government; (2) dependence on subsidies. Meanwhile, the social dimension is influenced by (1) The development of the number of fishermen; (2) The level of conflict. Lastly, the technological dimensions which influenced by (1) fishing vessel size; (2) Mechanical power, and institutional dimensions (1) The role of customary leadership, and (2) Fishermen's involvement in the process of preparing management regulations