Employing systematic experiments and comparing the CO2 absorption amount, absorption rate and CO2 loading of various amines and their mixtures, the optimal formula of blended amine solution is investigated. The results demonstrate the absorption characteristics of diethylenetriamine are the best, followed by monoethanolamine and methyldiethanolamine, while diethanolamine has no competitive advantage, neither in terms of the absorption amount and rate nor loading of CO2. The amine concentration has a significant influence on CO2 absorption, followed by formula and ratio, while the temperature and pressure affect little. The optimal formula of blended amine solution with the highest rate constant and activation energy of CO2 absorption was determined.