A quantitative study on the absorption of CO2 by aqueous solutions of N-methyldiethanolamine（MDEA）in a rotating packed bed（RPB）was presented in this paper.The diffusion-reaction process for CO2-MDEA mass transfer in the RPB is modeled according to Higbie’s penetration theory with the assumption that all reactions are reversible.The results from both experiment and model show that the intensification within the RPB is mainly achieved by the larger concentration gradient of the dissolvable gas in the liquid film.The frequent renewal of the film results in short lifetime of liquid film on packing surfaces and increases the mass transfer coefficient significantly.The mass transfer within the RPB is a dynamic process. The shorter the lifetime of liquid film，the larger the mass transfer coefficient.Experiments are carried out at various rotating speeds，MDEA concentrations，temperatures and gas/liquid flow rates.The validity of this model is demonstrated by the fact that the simulated values agree well with the experimental data.