The solubility of carbon dioxide (CO2) was investigated using three different 1-ethyl-3-methylimidazolium ([EMIM]) cation-based ionic liquids: 1-ethyl-3-methylimidazolium acetate ([EMIM] [Ac]), 1-ethy1-3-methylimidazohum chloride ([EMIM] [CI]), and 1-ethyl-3-methylimidazolium methyl sulfate ([EMIM][MeSO4]). The CO2 solubility data for the three ionic liquids were produced by measuring the bubble-point and cloud-point pressures of the CO2 + ionic liquid mixtures. The temperature range was from 303.15 to 403.15 K, and the pressure range was from 0.45 to 48.6 MPa. The experimental data provided results showing that the solubility of CO2 in ionic liquids increased with pressure, decreased with temperature, and was also affected by the different anions used in the experiment. The solubility is determined by CO2 mole fraction in ionic liquids, and the order of magnitude of the CO2 solubility was found to be [EMIM] [Ac] > [EMIM][MeSO4] > [EMIM] [CI]. For the correlation and calculation of the experimental data, we used the Peng Robinson equation of state, the conventional van der Waals one-fluid mixing rule, and the modified Lydersen-Joback-Reid method. The average absolute of pressure were 0.0231 for CO2 + [EMIM][Ac], 0.0141 for CO2 + [EMIM] [CI], and 0.0275 for CO2 + [EMIM][MeSO4] systems.