A new concept of using multiple apparent constant parameters plus sensitivity analysis was developed based on a modified Kent-Eisenberg model for predicting the carbon dioxide (CO2) solubility in aqueous 2-amino-2-methyl-1-propanol (AMP) solutions. Three apparent constants of amine protonation, dissociation and physical dissolution of CO2 were identified to be the most significant parameters in the system. Previously published data were used to determine these three constants utilizing a nonlinear least-squares technique. The predictions from the present model agree well with all 121 experimental measurements available in the open literature.