Absorption of carbon dioxide from flue gas was investigated in a hollow fiber membrane contactor using methyldiethanolamine + potassium glycinate (MDEA+PG) aqueous solutions. The experimental results showed that the CO2 removal efficiency increased with the membrane contactor length increasing. CO2 removal efficiency and the mass transfer rate of CO2 increased with the increase of liquid flow rate. CO2 removal efficiency decreased with gas flow rate increasing. CO2 removal efficiency decreased and mass transfer rate increased with the CO2 volume fraction inlet increasing. Comparing PG with monoethanolamin (MEA) as auxiliary absorbent, the hybrid solution of MDEA+PG was better than that of MDEA+MEA.