The influence of admixtures of chemically different polar organic solvents on the yield of distillates in atmospheric and vacuum distillation of crude oil has been studied. A comparative assessment of the compositions of asphaltenes isolated from vacuum residues has been made with the use of IR spectroscopy. The distillate recovery efficiency has been found to increase to the greatest extent in the presence of N-methylpyrrolidone as an additive during atmospheric distillation and E >-caprolactam in the case of vacuum distillation. However, the admixture of E >-caprolactam to crude oil does not provide an increase in aromaticity of vacuum-residue asphaltenes.