Solubility data of carbon dioxide (CO2) in poly(ethylene glycol) dimethyl ether (PEGDME) are presented at pressures up to about 50 bar and at temperatures between 303 K and 343 K. The solubilities of CO2 were determined by measuring the bubble point pressures of the CO2 + PEGDME mixtures with various compositions using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. To observe the effect of the PEGDME molecular weight on the CO2 solubility, the CO2 solubilities in PEGDME with two kinds of molecular weight were compared. As the equilibrium pressure increased, the CO2 solubility in PEGDME increased. On the other hand, the CO2 solubility decreased with increasing temperature. When compared at the same temperature and pressure, the PEGDME with a higher molecular weight gave smaller CO2 solubility on a mass fraction and molality basis, but gave greater CO2 solubilities on a mole fraction basis.