The purpose of this study was to determine the estimation of biomass, carbon stocks, oxygen production and the value of environmental services from mangrove tree stands in Rawa Aopa Watumohai National Park, Tinanggea District in helping the potential to control climate change. Biomass measurements were carried out by making 50×50 m plots of 15 plots divided into three different sampling locations. This tree stand calculation uses the allometric equation of mangrove tree species found in the measurement. The calculation of carbon stock was done by multiplying the biomass against the conversion rate of 0.47 (47%) while the estimation of carbon dioxide uptake was multiplied by the biomass value with a conversion rate of 1.4667 obtained from the photosynthesis equation. The results of this study indicate that the biomass content of mangrove tree stands in Rawa Aopa Watumohai National Park, Tinanggea District is 923.81 tons/hectare; carbon stock in mangrove stands is 434.19 tons/hectare; oxygen production is 95.91 tons/hectare; and carbon dioxide uptake in mangrove stands is 204.07 tons/hectare or 26.42 tons/hectare/year. Carbon dioxide environmental services are worth USD 34.37/hectare/year.