Thailand has high potential of biomass to utilize for energy. The processing of agricultural produces in the agro-based industries in Thailand results in remarkable amount of biomass residues. These residues are considered as waste and are, generally, disposed off through various methods such as open dumping or inefficiently combust as heat sources in industries. One of the most efficient uses of biomass is to convert them to high grade energy such as electricity. The objective of this study is to estimate potential of biomass to reduce the dependency of fossil fuel and the mitigation of CO2. Four biomass considered in this study are paddy husk, corncob, fuel wood and MSW. The biomass potential is estimated by basing on the present cultivate areas and crop yield area. Based on the biomass energy potential, the electricity generation capacity is estimated. At the end of 2025, the biomass based plants are expected to reduce the dependency of fossil-based plant for more than 5,000 MW.