One measure of increasing carbon sequestration areas is community forest conservation, which is the way to maintain common forest areas linking with human livelihoods. The first step towards implementing incentive mechanism of Reducing Emissions from Deforestation and Degradation (REDD) at the national level is to assess the amount of forest carbon. This is important for REDD inspections and subsequent funding from public funds or carbon markets. The objective is to find the carbon stock in soil, aboveground and belowground biomass for estimated carbon price in the community forest. The study site was carried out at Ban Phrao community forest, Sa Kaeo Province, East of Thailand. Field data were collected from temporary 16 plots the diversity of plant species, to assess forest biomass carbon storage based on the allometric equation, and to estimate the proportion of carbon contents in plant and soil by using CHN analyzer.