The invention relates to a method for increasing the content of asphaltene in low-asphaltene raw materials. The method comprises the following steps of: heating residual oil or deoiled asphalt, and then enabling the heated residual oil or deoiled asphalt to enter a thermal cracking factional distillation column to obtain thermal cracking produced oil, wherein the heating temperature ranges from 390 DEG C to 450 DEG C; and carrying out reduced-pressure factional distillation on the thermal cracking produced oil to obtain column bottom residues for blending matrix asphalt used for producing modified asphalt, wherein the residual oil is reduced-pressure residual oil with the atmospheric boiling point being higher than 350 DEG C, the reduced-pressure residual oil is obtained after gasoline, coal diesel and lubricating oil components are separated from thick crude oil through atmospheric and reduced-pressure distillation, and the residual oil contains 0.1-0.5% of asphaltene and 45-55% of colloid; or the residual oil is deoiled asphalt obtained after a heavy lubricating oil component is removed through solvent deasphalting, and the deoiled asphalt contains 0.1-0.5% of asphaltene and 50-60% of colloid. By using the method, the content of the asphaltene in the low-asphaltene raw materials is increased from 0.1-0.5% to 5-20%.