Experimental data are reported for adsorption from binary and ternary liquid mixtures p-xylene/m-xylene, p-xylene/ethylbenzene, ethylbenzene/m-xylene, and p-xylene/m-xylene/ethylbenzene on a KBa-Y zeolite at 25-degrees-C. In calculations of the difference of free energy of immersion for pure adsorbates in binary systems, three binary data have been found to be thermodynamically consistent. Based on the method of Price and Danner, predictions of adsorption equilibria for the ternary system p-xylene/m-xylene/ethylbenzene are also carried out by using only the parameters determined from the constituent binary pairs. Compared with the experimental data, the absolute average percent deviations of the predicted values of the surface excess are 6 and 8.3% for p-xylene and m-xylene, respectively. As a result, the correlations can be used to calculate the adsorption equilibrium for binary and ternary systems involving p-xylene, m-xylene, and ethylbenzene on a KBa-Y zeolite at 25-degrees-C.