We reported a coaxial,micro-dielectric barrier discharge(micro-DBD)reactor and a conventional DBD reactor for the direct conversion of methane into higher hydrocarbons at atmospheric pressure.The effects of input power,residence time,discharge gap and external electrode length were investigated for methane conversion and product selectivity.We found the conversion of methane in a micro-DBD reactor was higher than that in a conventional DBD reactor.And at an input power of 25.0 W,the conversion of methane and the total C2+C3 selectivity reached 25.10% and 80.27%,respectively,with a micro-DBD reactor of 0.4 mm discharge gap.Finally,a nonlinear multiple regression model was used to study the correlations between both methane conversion and product selectivity and various system variables.The calculated data were obtained using SPSS 12.0 software.The regression analysis illustrated the correlations between system variables and both methane conversion and product selectivity. We reported a coaxial, micro-dielectric barrier discharge (micro-DBD) reactor and a conventional DBD reactor for the direct conversion of methane into higher hydrocarbons at atmospheric pressure. These effects of input power, residence time, discharge gap and external electrode length were investigated for methane conversion and product selectivity. We found the conversion of methane in a micro-DBD reactor was higher than that in a conventional DBD reactor. At at input power of 25.0 W, the conversion of methane and the total C2 + C3 selectivity reached 25.10% and 80.27%, respectively, with a micro-DBD reactor of 0.4 mm discharge gap. Finally, a nonlinear multiple regression model was used to study the correlations between both methane conversion and product selectivity and various system variables. calculated data were obtained using SPSS 12.0 software.The regression analysis illustrated the correlations between system variables and both methane conversion and product selectivity.