The enhancement of CO 2 desorption from Nmethyldiethanolamine (MDEA) rich solution was investigated in ultrasonic microreactors. Under ultrasound irradiation, the rate of bubble growth increased significantly due to rectified diffusion and bubble coalescence. The measured CO 2 desorption rate was found to be obviously enhanced by ultrasound, being almost doubled at low temperature. The effects of various parameters on the enhancing effect of ultrasound were also investigated, including desorption temperature, solution flow rate, CO 2 loading, MDEA concentration, microchannel length and capillary diameter. The results indicated that ultrasound was more suitable to intensify the CO 2 desorption process at low temperature, by virtue of which the regeneration energy consumption and solvent loss could be efficiently reduced.