High surface area graphites with different amounts of oxygen surface groups were prepared, and characterized by temperature programmed desorption and thermogravimetry. The oxidation treatments with H2O2 and HNO3 resulted in a partial destruction of the carbon structure and in an increase of the content of the oxygen-containing groups, more evident in the sample treated with HNO3. The enthalpies of immersion of the samples in methylcyclohexane, toluene and mesitylene have proved that the surface chemistry of the graphites has a great influence on the adsorption of aromatic molecules. For all the samples the enthalpies follow the order methylcyclohexane < toluene < mesitylene. On the other hand, while the enthalpy of immersion in methylcyclohexane is independent on the content of oxygen surface groups, the areal enthalpies for the aromatic molecules, toluene and mesitylene, increase as the density of oxygen groups does. Moreover, this effect is more evident in the case of mesitylene.