A method for upgrading fluid catalytic cracking gasoline includes the following steps: cutting fluid catalytic cracking gasoline into light, medium, and heavy gasoline fractions; subjecting the medium gasoline fraction to an aromatization/hydroisomerization reaction in the presence of a catalyst to obtain a desulfurized medium gasoline fraction; and blending the light gasoline fraction, the desulfurized medium gasoline fraction and the heavy gasoline fraction to obtain upgraded gasoline; where, a cutting temperature of the light and the medium gasoline fractions is 35-60° C., and a cutting temperature of the medium and the heavy gasoline fractions is 70-160° C. The method according to the present invention not only can realize deep desulfurization of fluid catalytic cracking gasoline, but also can improve octane number significantly.