This study investigated the effects of gas components on the oxidation of Hg-0 by dielectric barrier discharge (DBD) non-thermal plasma (NTP) technology. The findings indicated that reactive species such as O-center dot and Cl generated by ionization of O-2 and HCl played dominant roles during oxidation processes. The presence of 50 ppm of HCl in N-2/O-2 atmosphere enhanced the Hg-0 oxidation, the complete oxidation of Hg-0 was observed by 6 kV of applied voltage. The presence of NO in the reactor decreased the Hg-0 oxidation efficiency due to the interference by NO reaction with O-center dot and O-3. The addition of 310 ppm of NO into the flue gas remained in 55% of Hg-0 oxidation efficiency. Water vapor inhibited Hg-0 oxidation, which was attributed to the consumption of reactive species and decomposition of HgOH. SO2 had a slight promoting effect on Hg-0 oxidation, compared with the absence of SO2, the oxidation efficiency increased by 2-8% with the addition of 100-200 ppm of SO2. This study leads to starting the development of a novel promising environmental technology for Hg removal in the flue gas. (C) 2015 Elsevier Ltd. All rights reserved.