As the ocean provides an environmental carrier for fisheries development, sustainable marine fisheries and marine environmental protection are highly synergistic and consistent. Facing traditional and emerging crises such as marine pollution, overfishing and climate change, China revised the Marine Environmental Protection Law in 2023. This article aims to evaluate whether the newly revised Marine Environmental Protection Law effectively responds to crises of sustainable development in marine fisheries and how it contributes to sustainable marine fisheries. The study has found that the 2023 revision enriches and improves China’s legal regimes on marine fisheries from multiple aspects, covering marine environmental supervision, marine ecological protection and the prevention and control of land-based pollution, engineering construction projects pollution, waste dumping pollution, vessel pollution and legal responsibility. The newly revised Marine Environmental Protection Law not only refines the institutional norms and intensifies the legal responsibilities of violations but also improves the systemic nature of the legislation, thus providing stronger legal guarantees for sustainable marine fisheries. However, there are also legislative shortcomings such as unclear connotations of the newly established legal regimes and insufficient response to overfishing and climate change. Nevertheless, China’s newly revised Marine Environmental Protection Law applies the methodology of integrated ecosystem management and comprehensively utilized regulatory measures such as command-and-control tools, honor encouragement and economic incentives to enhance its regulatory effect, also providing implications and insights for addressing the challenges of sustainable marine fisheries on a global scale.