Abstract: Methods for producing fuel distillates used as raw material in the production of fuel for engines or jet engines. The invention involves mixing residual petroleum raw material (oil fuel, tar) with sapropelite and with a fraction of thermo-cracking or hydro-cracking hydrogenated products having a boiling point of between 300 and 400° C. in an amount of between 1 and 5% relative to the weight of the residual petroleum raw material. The mixture is heated, homogenized at least twice in a dispersing agent at a temperature of between 85 and 105° C., and submitted to a thermo-cracking or hydro-cracking process. The fuel distillates (petrol, diesel fuel and gas oil) are then separated from the thermo- or hydro-cracking products. The invention thus pertains to the production of petroleum fuels and may be used in the oil-conversion industry.