The invention a semi-dry method desulfurization and denitrification integrated process and device in synergism with charged oxidation. The device comprises an absorption tower. A gradually-expanding section with the diameter gradually increased from bottom to top is arranged at the bottom of the absorption tower, a smoke inlet pipe is arranged at the bottom of the gradually-expanding section, an absorbent feeding port is formed in the wall of the gradually-expanding section and connected with an absorbent bin through a first screw feeder, multiple layers of atomizing nozzles are arranged at the lower middle part in the absorption tower, and a smoke outlet is formed in the top of the absorption tower. Openings of the atomizing nozzles are all formed upwards, the atomizing nozzles are all connected with a water tank through a water pump and further connected with an atomized compressed air pipeline, corona-charged rings are arranged above the atomizing nozzles respectively and supplied with power through a high-voltage power supply, and an oxidizing agent outlet pipeline is connected with the water tank or the atomized compressed air pipeline or the absorption tower.