Abstract: An experimental method,in which about more than 20 g feedstock was used, wasestablished for separating vacuum residue(VR ).The VR of Daqing,Guanshu and Liaohe wereseparated into eight-fractions respectively by precipitation with n-heptane and n-butanol and liq-uid chromatography with Al_2O_3 column. The eight-fractions were called Saturates,light , middleand heavy aromatics,light,middle and heavy resins and asphltene.The structural parameters ofeight-fractions of three VR were calculated by the Brown-Lander mothed according to the resultsof relative molecular weight,elemental analysis and H-NMR,the results indicated that eachfraction was substantially different in structure.