Abstract: To investigate the influence of wettability of mixed alcohol amine absorbents on the CO₂ mass transfer performance in membrane gas absorption process, the wetting properties and wetting rate of two mixed alcohol amine absorbents-MDEA (N-methyldiethanolamine)+MEA (monoethanolamine) and MDEA+TEA (triethanolamine) on the polypropylene hollow fiber membrane were determined by contact angle test and soaking test, and the mass transfer rate of CO₂ under different wetting degrees was measured by absorption test. Results show that both the wetting property and wetting rate of MDEA+TEA on PP hollow fiber membrane are higher than that of MDEA+MEA at the same concentration and solute ratio. The wettability of the same mixed alcohol amine on PP hollow fiber membrane increases with rising solute ratio (w(MDEA):w(MEA)/w(TEA)). Comparative tests indicate that the decrease of CO₂ mass transfer rate is caused by the wettability of mixed alcohol amine on the membrane, and the higher the wettability is, the lower the CO₂ mass transfer rate would be.