Abstract: H₂S and CO₂, two harmful acid waste gases, often co-exist in important chemical production such as coal-chemical industry, natural gas chemical industry and petrochemical industry, causing corrosion of industrial equipment and pipelines, and must be treated innocuously. Co-conversion of H₂S-CO₂ mixed acid gas to syngas has been carried out using dielectric barrier discharge (DBD) plasma-catalysis, which renders the highly corrosive and toxic H₂S and greenhouse gas CO₂ harmless, and produces syngas. The effects of various parameters of the DBD plasma on the reaction of one-step conversion of H₂S-CO₂ to syngas were studied. Moreover, a comparative study of the different parameters of DBD plasma was carried out. The intrinsic correlation between the reaction performance of syngas production via H₂S-CO₂ conversion and these parameters, including specific energy input (SEI), discharge shape, discharge frequency, discharge gap and discharge length, was investigated and revealed. On this basis, a multi-tube parallel DBD plasma reaction system was designed and constructed.