Liquid-liquid equilibrium data for the ternary systems of toluene+water+propionic acid, o-xylene+water +propionic acid, methyl isobutyl ketone+water+propionic acid, ethyl acetate+water+propionic acid, and 1-butanol +water+propionic acid were measured at 25 ℃ and atmospheric pressure. The reliability of the experimental tie-line data was ascertained by means of the Othmer-Tobias, Bachman-Brown, and Hand correlations. For the extraction effectiveness of solvents, the distribution and selectivity curves were plotted. In addition, these experimental tie-line data were also correlated with NRTL and UNIQUAC models.