Legislating for the ecosystem approach to fisheries (EAF) is complex, due to the holistic nature of the EAF involving multiple factors that underpin the social, economic, environmental, and institutional aspects of fisheries sustainability. These factors include ecosystems integration, risks, inter-sectoral collaboration, research, participatory processes, monitoring, control, surveillance, and enforcement, among others. To assess how the EAF is being implemented through national policy and legal frameworks, FAO developed "A diagnostic tool for implementing an ecosystem approach to fisheries through national policy and legal frameworks". The present legal report on the EAF used the diagnostic tool to assess the alignment of selected policy and legal instruments of Thailand with the EAF. This assessment analysed the extent to which 82 EAF legal requirements, which are considered the minimum standards in legislating for the EAF, are reflected in Thailand's policies and legislation relevant to the fisheries sector of the country and other relevant sectors (such as environment, wildlife, ecosystems, and maritime affairs). Based on this preliminary diagnosis, gaps were identified in the assessed instruments, and recommendations were made for improving the implementation of the EAF. This report was elaborated following a participatory approach with the involvement of the national competent authorities of Thailand. Drafted in July 2021, the report was submitted to the national authorities of Thailand in October 2021 and endorsed in March 2022.