Abstract: Simultaneous desulfurization and denitrification of marine diesel exhaust was carried out by coupling the dielectric barrier discharge (DBD) with corona discharge pulse (CDP) to generate non-thermal plasma (NTP). The effect of various gas components in the exhaust gas and the amount of monoethanolamine, discharge current, gas flow rate and other factors on the desulfurization and denitrification were then investigated and the mechanism of denitrification by NTP was discussed. The results show that when the total gas flow rate is 650 mL/min, applying 1.67 A current discharge and adding 0.48% monoethanolamine to the simulated marine diesel exhaust (N₂/O₂/SO₂/NO_x/CO₂/H₂O) can weaken the negative effects of oxygen and water vapor on the denitrification. Besides, monoethanolamine can also weaken the negative effects of carbon dioxide by absorbing carbon dioxide from the exhaust and the final denitrification rate reaches 94%. Meanwhile, a high desulfurization rate (97%) is also achieved, as monoethanolamine can absorb sulfur dioxide rapidly, which is almost unaffected by any exhaust gas components.