In this dissertation six deep eutectic solvents in various molar ratios: ChCl-Gly 1:1,5, ChCl-Gly 1:2, ChCl-Gly 1:3, ChCl-EG 1:2, ChCl-EG 1:3 i ChCl-EG 1:3 were prepared, and characterization of their physicochemical properties essential for the extraction process were made. The liquid-liquid equilibria for the ternary systems hydrocarbon – pyridine or thiophene – eutectic solvent were determined. The hydrocarbon was varied between n-hexane, n-heptane, i-octane or toluene. Equilibria were successfully described by NRTL and UNIQUAC activity coefficient models, but the preference can be given to the UNIQUAC model. The solubility of pyridine (max. 78 %) in the deep eutectic solvent was significantly higher than the solubility of thiophene, which did not exceed 10%. Mixing of hydrocarbons and deep eutectic solvents was not observed, so it is concluded that the tested eutectic solvents are selective for thiophene and pyridine, with affinity for denitrification. In an attempt to develop alternative methods that meet the criteria of 'green' technology in gasoline production, the possibility of using prepared eutectic solvents for desulfurization, denitrification and dearomatization of model and real FCC-gasoline by liquid-liquid extraction under atmospheric conditions was investigated. Model gasoline is a solution containing 26 % of n-hexane, 26 % of n-heptane, 26 % of i-octane, 10 % of toluene, 6 % of pyridine and 6 % of thiophene and its composition mimics FCC-gasoline. From the preliminary experiments, the working conditions of the extraction experiments were designed. For the purpose of analysis of the raffinate phase composition after extraction, a gas chromatography method was developed. The best mass ratio of solvent : model gasoline was determined; it amounted 1:1 in all systems. With a lower mass ratio, in multistage extraction, the same extraction efficiency was achieved as with the optimum one. The extraction capacity of the solvent was reduced without purification of the solvent between the extraction steps. Solvent regeneration was successfully done by simple vacuum evaporation of the dissolved components between stages, without a loss in extraction efficiency. All tested eutectic solvents showed higher affinity for denitrification than desulfurization and dearomatization. ChCl-Gly 1:3 was selected from the group of glycerol-based solvents, and ChCl-EG 1:3.5 was selected from ethylene glycolbased solvents. The results showed that the denitrification efficiency increased with the content of hydrogen bond donors in deep eutectic solvent. The same trend of behavior was present in real gasoline samples.