Abstract: In order to study the primary and secondary factors affecting the discharge characteristics of DBD plasma assisted coal combustion, and to obtain the best factor level combination scheme to improve the discharge characteristics. The DBD reactor is characterised by a flat plate structure, which serves the purpose of assisting combustion, three factors and three levels were selected, the number of experiments was reduced from 27 to 9 by orthogonal experiment. The results show that the voltage level and electrode spacing are the most significant factors affecting the discharge power and the amount of transferred charge, and the best factor level combination scheme for improving the discharge power and the amount of transferred charge is A₃B₃C₁ and A₃B₃C₂. The research results can provide some reference value for the optimization of DBD plasma assisted combustion reactor.