This study aims to compare and analyze the fisheries laws and institutions of South and North Korea and to propose legal measures for sustainable fisheries development and cooperation. South Korea, based on a market economy, operates its fisheries sector through scientific fisheries management, IUU fishing prevention, Total Allowable Catch (TAC) expansion, and climate change adaptation while complying with international regulations. In contrast, North Korea maintains a centrally planned economy in its fisheries sector, with structural limitations such as the absence of a fishing permit system, non-compliance with UNCLOS, and deficiencies in seafood hygiene and quality management systems. This study proposes legal and institutional reforms to address these challenges, including revising North Korea's fisheries laws to align with international standards, the establishment of a joint fishing zone, an enhanced monitoring system for IUU fishing prevention, and cooperative climate change adaptation and marine environmental protection initiatives. Additionally, it emphasizes the need to improve seafood distribution, and certification systems to facilitate inter-Korean trade and improve competitiveness in the global market. Inter-Korean fisheries cooperation should not be based on the unilateral imposition of one system over the other, but rather on legal and institutional alignment with UNCLOS and the Sustainable Development Goals (SDGs) to ensure effectiveness. By addressing these legal and regulatory disparities, inter-Korean cooperation can contribute to sustainable fisheries development on the Korean Peninsula and the stabilization of the Northeast Asian maritime order.