This study was conducted to investigate the decomposition of volatile organic compounds in air by the rotating arc plasma system. The rotating arc plasma decomposed benzene, toluene, and m-xylene (BTX) gases diluted in air. The effects of the gas flow rate and arc rotation speed on conversion rate and energy efficiency were evaluated by high speed images and Fourier transform infrared spectroscopy. Perfect conversions of toluene and m-xylene into environmentally benign species were achieved at the lowest waste gas flow rate of 20 L/min, while the conversion rate of benzene was 79% under the same operating conditions due to the highest chemical bond strength of benzene among BTX. Although the conversion rate decreased with increasing the gas flow rate, the energy efficiency had an optimal gas flow rate, which influenced arc rotation speed. In addition, the oxidation rates of BTX were examined based on analysis of carbon oxides generated under different operating conditions. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.