The excess molar enthalpies (H-E) of carbon dioxide + isobutyl alcohol. and carbon dioxide + (ethanol + water) systems were measured in the supercritical region of carbon dioxide over the entire composition range at 308.15 K and at pressures from 7.5 to 8.5 MPa using a flow-type isothermal microcalorimeter. A strong dependence of HE on pressure at this area was observed. The correlation of the excess molar enthalpies was made using a composition-dependent equation composed of two polynomial expressions.