The solubilities of carbon dioxide in the aqueous potassium carbonate (K2CO3) solutions and potassium carbonate-poly(ethylene glycol) (PEG) solutions were measured at 298.2 and 323.2 K with a CO2 partial pressure range of 5 kPa to 2 MPa. The concentrations of the aqueous mixtures by mass were 5% K2CO3, 5% K2CO3-15% PEG, 5% K2CO3-30% PEG, 10% K2CO3 and 10% K2CO3-15% PEG. The experimental solubility results were presented by the mole ratio of CO2 and K2CO3 contained in the liquid mixture. The addition of PEG to 5 mass% K2CO3 solution rather lowered the solubility of CO2 at a constant temperature and pressure within the CO2 partial pressure range of 5 kPa to 2 MPa. The loadings of CO2 decreased with increasing temperature from 298.2 to 323.2 K.