Background/Question/Methods East Asia is composed of China, Japan, North and South Korea, and Mongolia. It has diverse climates, and thus produces a diverse range of ecosystems. This region has also experienced a long time of landuse change and recent large-scale afforestation and reforestation practices. These make this region unique in the terrestrial carbon budgets. In this paper, we quantify forest biomass carbon sequestration and its changes between 1970s and 2000s, by investigating changes in biomass carbon stocks in each country. We also evaluate effects of major forestry practices on national carbon sequestration, and predict potential of carbon sequestration in the future. We use a consistent method of biomass expansion factor (BEF) and well-documented national forest inventories to estimate the changes in biomass carbon stocks for each country. We use an age-class based model to predict the carbon sequestration potential. Results/Conclusions Our data showed that over the last 4 decades, East Asian forests are a big biomass carbon sink with a mean sequestration rate of 0.103 PgC/yr, and this sink increased significantly from 0.056 PgC/yr in the 1970s to 0.154 PgC/yr in the 2000s. Our model predicted that East Asian forests will continue to sequester carbon due to increased plantation area and enhanced forest growth. For example, according to our model, China’s forests will be a net sink of 0.15 PgC/yr between 2005 and 2050. In addition, we will assess forestry development strategies announced by these countries, and provide suggestions on implications of the strategies to the policy-makers.