The macrokinetics of NO oxidation by vaporized H2O2 association with ultraviolet light was evaluated. The effects of various influencing factors on the NO oxidation rate were investigated, such as the H2O2 concentration, the H2O2 pH, the reaction temperature, the UV energy density, the UV light wavelength, the coexistence of gases (SO2 and O-2), and the radical scavenger tert-butanol. The NO oxidation was conformed to a pseudo-first-order kinetics pattern under the experimental conditions. The rate constants determined at 373-413 K fitted the Arrhenius equation well, yielding an apparent activation energy of 20.8 kJ/mol. The experimental results indicated that both UV power density and UV light wavelength exhibited significant influences on NO oxidation, and decreasing pH and increasing O-2 concentration could enhance NO oxidation. A mechanism of NO oxidation was also proposed.