In this paper, a quick and direct method has been developed for the quantitative estimation of total aromatics and saturates in a vacuum gas oil (VGO) fractions boiling range (370-560 degrees C), using H-1 NMR spectroscopic techniques. The method is based on the estimation of the average alkyl chain length of substituents on aromatics and the relative group molecular weight of aromatics and saturates. The total aromatics are estimated from the derived equation, which takes into account the relative distribution of CHn (n = 0, 1, 2, 3) groups of aromatics substituents and saturates. The! exact assignment of aromatics substituents of alpha-CHn (n = 1, 2, 3) has been performed by the application of H-1/C-13 multipulse NMR techniques, such as DEPT-135 and 2D HSQC (edited) (heteronuclear single quantum coherence). The results obtained for several VGO samples from different sources have been in close agreement with those from the open chromatography method (ASTM D-2549-91) and the thin-layer chromatography-flame ionization detection (TLC-FID) method (IP-469).