This paper extended the experimental results of carbon dioxide partitioning in gas/liquid equilibrium with a NaCl-H2O-monoethylene glycol (MEG) mixed solvent. The experiments were conducted systematically at 3-70 degrees C, 0-6.0 m NaCl, and 0-99 wt % MEG concentrations. CO2 partitioning to the NaCl-H2O-MEG solution is complicated due to nonideal behavior in the solvent. A self-consistent activity model is proposed to describe the effect of monoethylene glycol (MEG) on CO2 partitioning in gas/MEG/water/salt solutions using pure H2O as the reference state. Pitzer theory was used to calculate the effect of salt, and a semiempirical equation was applied to correlate the effects of MEG at different temperatures and ionic strengths. The equation is applicable to CO2 partitioning at 0-6 mol of NaCl and 0-97% MEG mixed solution at 0-90 degrees C. This model can be incorporated with Pitzer type activity coefficient models to predict the solubility of carbon dioxide in the presence of MEG and salt solutions.