Carbon sequestration via carbon capture and storage (CCS) method is one of the most useful methods to lower the CO2 emission in the atmosphere. Ethylenediamine (EDA) and triethylenetetramine (TETA) modified mesoporous carbon (MC) has been successfully prepared as CO2 storage materials. The effect of various concentrations of EDA or TETA added to MC as well as activated carbon (AC) on their CO2 adsorption capacity were investigated using high purity CO2 as feed and titration method to quantitatively measure the amount of adsorbed CO2. The results showed that within 60 min adsorption time, MCEDA49 gave the highest CO2 capacity adsorption (19.68 mmol/g), followed by MC-TETA30 (11.241 mol/g). The improvement of CO2 adsorption capacity at low TETA loadings proved that the four amine functional groups in TETA gave advantages to CO2 adsorption. TETA functionalized MC has a potential to be used as CO2 storage materials as it is used at low concentration. Therefore, it is more benign and friendly to the environment.