This study was performed to estimate the potential amount of forest carbon storage in future climate using forest cover map, National Forest Inventory (NFI) data, and Hydrological and Thermal Analogy Groups (HyTAGs). The regression models were developed to predict forest volume, diameter at breast height (DBH) and number of trees (N) using NFI data. The potential distribution map of forest cover after 50 and 100 years was prepared using HyTAGs. For the area where forest cover would be changed after 50 years, the volume was calculated using the regression model with DBH₅₀ and N₅₀ after 50 years. The volume of unchanged forest area can be predicted with DBH_k+50 and N_k+50 adding 50 years to the present age k. Amount of forest carbon storage was calculated from the forest volume using the wood basic density, biomass expansion factors and 0.5 of carbon conversion index. Likewise, the forest volume and carbon storage after 100 years followed the same process. As a result, it was predicted that the forest cover would be changed gradually into the deciduous broad-leaved forests for coming 100 years. The forest carbon storage would increase by approximately 542 MtC for coming 50 years, even if the forest cover is largely changed in South Korea. The change in forest carbon storage after 100 years showed the decrease to 2,469 MtC.