The effects of CH4/Ar mole ratio, feed flow rate, input voltage, and reactor configuration were investigated for the direct conversion of CH4 into higher hydrocarbons with a coaxial, dielectric barrier discharge (DBD) microplasma reactor at atmospheric pressure. The results indicated that the conversion of CH4 and the selectivies of C2H6 and C3H8 increased with CH4/Ar mole ratio at a fixed feed flow rate. The DBD microplasma reactor with a smaller discharge gap was favorable to methane conversion. Meanwhile, a simplified global kinetic model according to methane concentration was used to compare methane conversion behavior in different microplasma DBD reactors. The kinetic model showed that the conversion of CH4 was an exponential function of the plasma energy for a lower CH4 inlet concentration and a linear function of the input energy for a high CH4 inlet concentration, respectively. The kinetic model also implied that a microplasma reactor with a smaller discharge gap had higher energy efficiency. (C) 2013 Elsevier B.V. All rights reserved.