Carbon storage at mangrove ecosystem is one of the largest compared between any vegetated ecosystem. Palopo City is one of the cities bordering teh Gulf of Bone and still have secondary mangrove ecosystem. This ecosystem become a good vegetated area which can provide environmental services in the form of CO2 uptake around Palopo City. This study aimed to analyze carbon storage at mangrove ecosystem at Palopo City. Furthermore, the value of carbon storage converted to CO2-eq value which described uptake at mangrove ecosystem. Method of this research is non destructive sampling and used existing allometric equations. Data collection carried out by measuring tree diameter in sampling plot 25 × 25 m with space between plot is 100 m. Result of this study showed that average of above ground carbon is 82.34±16.92 ton/ha equal to 301.90±62.03 ton/ha CO2-eq. The sequestration of CO2 based on each mangrove species at study area is Avicenia marina55.26 ton/ha, Rhizophora apiculata 497.13 ton/ha, Rhizophora mucronata 2259.49 ton/ha, Rhizophora spp. 1975.62 ton/ha, Sonneratia alba 4268.43 ton/ha, Xylocarpus granatum 1.19 ton/ha.