Pilot tests of a combined process for enhanced oil recovery developed on the basis of inorganic gelforming and oil-displacing compositions were performed in the Las-Eganskoe oil field, Western Siberia. The components of the surfactant-based oil-displacing composition were nitrogen compounds that serve in dilute solutions as a nutrient substrate stimulating the growth and oxygenase activity of reservoir biocenosis. Metabolic products that increase the oil-washing efficiency of the composition accumulate during the oxidation of petroleum hydrocarbons. The complex technology suggests the enhancement of oil recovery via an increase in the reservoir sweep efficiency by flooding with the gel-forming composition and in the oil displacement efficiency by the detergent composition and the microbiological component. Field tests of the method were performed on three test areas of the Jurassic horizon of the Las-Eganskoe oil field.