The separation of cresol isomers was investigated by adsorption chromatography in a chromatogaphic media of Lichroprep SI 100. The eluent was composed of n-hexane and ethyl acetate. Adsorption isotherms for cresol isomers onto silica gel in n-hexane at 30$^\circ$C were measured in the concentration range of 1-30mol/m3. Most of the models for the single for the single component system well predicted the experimental results. The affinity of cresols to the absorbent was increased in sequence of o-, m-, and p-cresols. For binary ststem, the competitive adsorption was quantitatively stuied by introducing the competitive adsorption coefficients. The relative affinity of p-cresol with respect to silica surface was larger than those of the other two components. The models using the multicomponent experimental data rather than those using the parameters obtained from the single component system well predicted the experimental results. For the sparation of m-/p-cresols mixture, inductive adsorption by o-cresol was used. As the concentration of 0-cresol increased, the separability of that mixture became large. Adsorption characteristics of cresol isomers in adsorption chromatograhpy were investigated in system where the binary elunet containing ethyl acetate as a modifier in -hexane was used. The method of moment was used to estimate the equilibrium constant and the rate parameters, i.e., the intraparticle mass transfer coefficient and the axial despersion coefficient. The agreement between the experimental. and theoretical results calculated by the orthogonal collocation method was excellnt. The equilibrium constant and rate parameters for each cresol were empirically correlated with eluent composition. As the eluent composition increased, the retention time and the front of response curve became faster and sharper, respectively. By using the modifier in the weak solvent, the mixtures of 0-/m-cresols and o-/p-cresols were easily separated wheras that of m-/p-cresols was...