Theoretical analysis of the electron energy distribution function by the Boltzmann equation and experimental investigations into the effect of hydrocarbons (methane, acetylene and ethylene) on NO removal efficiency are presented at varying temperatures. The experiments were carried out using dielectric barrier discharge plasmas at 298, 363 and 403 K, respectively. Ethylene greatly enhanced NO conversion because of its stronger affinity for the O radical. NO conversion in the presence of methane and acetylene was much lower than with ethylene at all temperatures. With an increase in temperature, E/N increased, the molecular ionization strengthened and the electron mean energy increased, resulting in more active species generated through ionizing and exciting reactions at the same energy density. High-energy electrons accelerated the decomposition rate of hydrocarbons, and the rate constants of some major reactions were increased, producing more strong oxidizing radicals (HO2). Therefore, NO removal efficiency was increased when the temperature was higher.