This paper reports the results of a new experimental study of surface tension for the ternary mixtures of water/acetonitrile/2-propanol. Correlating the excess surface tension of the above-mentioned binary and ternary systems was performed with empirical and thermodynamic based models. The methods of Pando et al. and Ku et al. were used to correlate the ternary surface tension data. The ternary surface tension data were well-correlated using pair additivity and rational functions as the ternary term. The results provide information on the molecular interactions between the unlike molecules that exist at the surface and the bulk.