The workshop titled “Key Indicator Species and Habitats for Marine Biodiversity Change in East Asia,” convened in Jeju, Republic of Korea, from 28th to 30th November 2022, facilitated the exchange of research on key indicator species among scientists from China, Japan, the Republic of Korea, Russia, and Southeast Asian countries. This policy brief presents key findings on key indicator species, ecosystem types, and pathways leading to marine biodiversity changes in East Asia. It aims to provide policymakers with actionable recommendations to enhance biodiversity conservation in the region.