Abstract: An experimental investigation on CO₂ reforming of CH₄ to synthesis gas was performed by a novel atmospheric pressure plasma jet, which is initiated by an alternating current of 50Hz and a high ratio transformer. The plasma jet proved to be a stable and uniform atmospheric pressure discharge that held the advantages of both thermal and non-thermal plasma. The effects of discharge distance, CH₄/CO₂ mol ratio in the feed, feed flow rate and discharge power on the reforming reaction were investigated. The results showed that the products of the reforming reaction are simple, including H₂, CO, a small amount of H₂O and carbon powder. The optimal discharge distance between two electrodes is 9mm and the optimal CH₄/CO₂ mol ratio is 4/6. When the flow rate is 1000mL/min and the discharge power is 88.4W, the conversions of CH₄ and CO₂ are 94.99% and 87.23%, respectively, which are higher than those via other plasmas. The conversions of CH₄ and CO₂ increase with increasing the discharge power and decrease with increasing the flow rate. Current process is more advantageous in treatment capacity and conversion ability for carbon dioxide reforming of methane than other plasma systems.