Basic rules of NO oxidation by a Fe2+/H2O2/AA directional decomposition system were researched based on the technical background of flue gas NOx removal. Effects of gas-liquid interfacial area, main gas, and solution parameters on NO oxidation efficiency () were analyzed. The results showed that adequate contact area was the precondition for high by a Fe2+/H2O2/AA system. decreased with the increase in NO concentration, which illustrated that this method would be efficient in oxidizing NO at a low concentration. tended to decrease linearly with the growth in gas flow, however, the NO oxidation rate (v) rose with the increase in NO concentration and gas flow. increased with the initial concentrations of H2O2 and Fe2+, but the amplitude decreased. Controlling the initial concentrations of H2O2 and Fe2+ to achieve reasonable synergies between generation rate and consumption rate of OH could weaken the invalid consumption of reactants. increased with the increase in temperature in the range 30-60 degrees C, but it nearly did not change with temperature after 60 degrees C. This oxidation technology and the traditional wet flue gas desulphurization technology exhibited temperature synergy. Under typical pH of wet desulphurization, and H2O2 consumption rate did not change obviously.