Deep desulfurization of coked gasoline was investigated by oxidation-extraction process with quaternary ammonium phosphomolybdate and formic acid as catalysts, hydrogen peroxide as the oxidant and furfural as the extractant. The effects of the oxidant volume, catalyst amount, extractant volume, reaction time and temperature to the desulphurization of coked gasoline were investigated. Improved desulphurization capacity of catalytic oxidation-extraction process for coked gasoline was obtained by optimizing the process conditions. Therefore, optimum conditions have been got in the actual desulfurization process of coked gasoline. The optimum technological conditions are as following: reaction time is 60 min, reaction temperature is 70 ℃, oxidant volume is 2.5 mL, extractant volume is 50 mL, catalyst amount is 0.4 g.