The article presents viscosity measurements on mixtures of poly(ethyleneglycol) 200 (PEG 200) saturated with supercritical CO2, along three isotherms, at approximately 313 K, 333 K and 348 K, and pressures up to 25 MPa. The measurements have been performed with a previously described vibrating wire instrument. The results show a steep initial viscosity decrease with increasing pressure of CO2, followed by a flatter zone, extending up to 25 MPa. This behavior, which is quantitatively temperature dependent, seems to be closely related to the solubility of CO2 as a function of pressure. The experimental method for the determination of the viscosity requires the density of the samples. For this purpose, the density data for the mixtures were calculated from phase equilibrium studies by Gourgouillon and Nunes da Ponte, using the Sanchez-Lacombe equation of state. The measured viscosity data for CO2 saturated PEG 200 solutions were then correlated using the Kelly-Bueche theory.