<p>By conducting an assessment of the ecosystem approach in the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ agreement) adopted in 2023, this paper aims to explore to what extent the ecosystem approach promotes the biodiversity governance centered on marine ecosystems. This paper begins by examining the relevant terms, definitions and elements of the ecosystem approach, followed by an analysis of why it constitutes an approach rather than a principle, setting the groundwork for subsequent research. Concrete analysis is then conducted on the relevant negotiation processes, final provisions and their interrelationships concerning various subject matters of the ecosystem approach in the BBNJ agreement. The conclusion reached is that the provisions on the ecosystem approach in the BBNJ agreement are of positive significance and conducive to achieving the objectives of the agreement. However, challenges exist in the future application of the ecosystem approach under the BBNJ agreement, including difficulties in defining the ecosystem approach, limitations on its scope of application, issues of overlapping application, lack of operational guidelines, and difficulties in its application within international jurisprudence. To promote the effective implementation of the ecosystem approach in the BBNJ agreement, consideration may be given to identifying its core elements, motivating Contracting Parties, enhancing coordination with relevant legal instruments and frameworks and relevant global, regional, subregional and sectoral bodies; establishing an implementation guide under the leadership of the Scientific and Technical Body, and developing systematic adjudication rules.</p>