Excess molar enthalpies, H-E, of binary mixtures of 1-octanol with ethylbenzene, ethyl benzoate, acetophenone, anisole, or methanol have been measured at 298.15 K under atmospheric pressure using an isothermal microcalorimeter. The experimental HE values are positive for all the binary mixtures over the entire range of compositions. The experimental data have been correlated with the modified Redlich-Kister polynomial equation. The results were qualitatively interpreted in terms of thermodynamic molecular interactions between the mixing components.