Systems of the coking gasoil type with residual and distillate cracking residues were investigated by electrophysical methods. Electrical processes, in particular, electrostatic blocking of high-melting components and formation of asphalt-resin complexes on electrically active centers, as well as mechanical factors, are responsible for the synergism and depressant activity. At 25-30 wt. % concentrations of additives in the mixtures investigated, a depressant effect was revealedfor the first time..