A strong ionization dielectric barrier discharge was used to produce a high concentration of reactive oxygen species that were then injected into a simulated flue gas in a duct to remove SO2 by oxidation. Sulfuric acid (H2SO4) was produced through the following two reactions: (1) O-3 oxidation of SO2-SO3, which then reacted with H2O to produce H2SO4; and (2) reaction of O-2(+) with H2O to produce center dot OH radicals, which then rapidly and non-selectively oxidized SO2-H2SO4. When the molar ratio of reactive oxygen species to SO2 was 4: 1, the SO2 removal efficiency was 94.6%, the energy consumption per cubic meter of flue gas was 13.3 Wh/m(3), the concentration of recovered H2SO4 was 4.53 g/l, and the H2SO4 recovery efficiency was 28.8%. The H2O volume fraction in the simulated flue gas affected the SO2 removal efficiency, whereas the O-2 and CO2 volume fractions did not. These results prove that oxidation by reactive oxygen species is a feasible method for flue gas desulfurization.