Abstract: Dielectric barrier discharge (DBD) technology is a kind of low-temperature plasma technology which is often used in the removal of pollutants in flue gas. The effect of nitric oxide removal by DBD was studied, and the influences of oxygen content, ethylene content and the addition of activated carbon in the discharge interval on the removal efficiency of nitric oxide were analyzed. The results show that when the oxygen content is less than 3%, the increase of oxygen promotes the removal of nitric oxide, while under the oxygen content of more than 3%, the increase of oxygen will produce excessive oxygen free radical (·O), which inhibits the removal of nitric oxide. The removal efficiency of nitric oxide can be improved by adding activated carbon and ethylene. Through the combination of DBD, activated carbon and ethylene, the removal efficiency of nitric oxide can go up to 90%, and especially the addition of ethylene can promote the removal of nitric oxide.