This work continues our studies on the excess thermodynamic properties for ternary mixtures containing ester, 1-alkanol and alkanes. We present excess enthalpy data for the ternary system: butyl butyrate + I-octanol + octane at the temperature 298.15 K and atmospheric pressure. Excess molar enthalpies measurements were made using a Calvet microcalorimeter. The experimental results for the binary mixtures were fitted using a Redlich-Kister variable-degree polynomial equation. The ternary excess enthalpies were correlated using the Cibulka equation. Experimental values were compared with the predictions obtained by several contribution models. The prediction of several empirical equations was also tested. (C) 2003 Elsevier B.V All rights reserved.