Abstract:As the only inland sea of China, Bohai Sea has been regarded as the integrated part of the national territorial space toward green and high-quality development in the new era. The comprehensive environmental treatment in Bohai Sea has achieved noticeable progress, but the problems remain. The trend of biological and ecological degradation of Bohai Sea has not been fundamentally curbed. Guided by President Xi Jinping thought on ecological civilization and on building a maritime community with a shared future, China should join into the Implementation Plan for the United Nations Decade of Marine Science for Sustainable Development (2021-2030), and manage to formulate Bohai Sea Decade Action Plan for Green and High-quality Development. The proposed action plan should aim at establishing "Clean Bohai Sea", "Ecological Bohai Sea", "Low-carbon Bohai Sea", and "High-quality Bohai Sea", and enhancing special projects in terms of science and technology, ecology, industry, and management. China would set up a typical module of regional sea sustainable development worldwide.