An analytical procedure has been developed which enables rapid quantitative determination of the total aromatic components in the petroleum fraction, used in the production of lubricating motor oils. The method utilizes the ultraviolet-diode array (UV-DAD) and refractive index detector (RI) signals derived from a gel permeation ghromatography analysis (GPC). It provides information about the concentrations of the aromatic compound groups (mono-, di-, tri-, thioaromatics) based on the differences in their absorbances in the ultraviolet (UV) spectrum. The method call be also applied for the determination of the distribution of these groups along the molecular weight range.