Five choline-based amino acid ionic liquids ([Cho][AA]s) are prepared by neutralization between choline hydroxide and amino acids with different molecular weight and alkalinity. Solubility of CO₂ in 30 wt% aqueous solutions of these five [Cho][AA]s has been measured at temperatures from 303.15 to 333.15 K and pressures up to 7 bar. Based on the zwitterion mechanism, the solubility of CO₂ in aqueous [Cho][AA]s solutions is correlated with a reaction equilibrium thermodynamic model (RETM). The corresponding thermodynamic parameters, such as Henry’s law constants, reaction equilibrium constants, and enthalpy of physical dissolution and chemical reaction are all calculated and compared to evaluate the CO₂ absorption performance in aqueous solutions of five [Cho][AA]s. Meanwhile, the recyclability of the aqueous solution with 30 wt% [Cho][Lys] has been also investigated.