This study examines the role of the Trilateral Cooperation Secretariat (TCS) in addressing food security issues in East Asia, focusing on the decline in China's domestic food supply and demand, Japan's dependence on food and energy imports from the Japan-EU Economic Partnership Agreement -Japan, and the escalating food waste problem in South Korea from 2005 to 2023. This study explores how the Trilateral Cooperation Secretariat (TCS) contributes to managing common challenges in regional food security. A qualitative method with a literature review approach was used to analyze primary and secondary sources such as official documents, joint statements, reports, and academic literature. The findings show that the TCS plays a facilitating role in enhancing policy coordination, promoting information exchange, and encouraging joint initiatives among the three countries. Through the framework of international agreements, the TCS contributes to institutionalizing cooperation, while Nye's regionalism perspective highlights how shared interests and interdependence drive joint efforts to ensure food stability. However, this study also identifies limitations in the depth of cooperation due to political tensions and differences in national priorities. The study concludes that TCS, despite its limitations, serves as an important platform for operationalizing the policies of China, Japan, and South Korea for implementation in East Asia. Keywords: Trilateral Cooperation Secretariat, International Agreement, Regionalism (Joseph S.Nye), Food Security.