The invention discloses a PLC (Programmable Logic Controller) controlled efficient denitration device which comprises a device main body, a cleaning tank and a reaction tank. The device is characterized in that the cleaning tank is arranged at the lower part inside the device main body. According to the efficient denitration device, the reaction tank is arranged on a smoke inlet tube, a reaction column is arranged inside the reaction tank, an ozone generator is adopted to feed ozone into the reaction column to be reacted with smoke, then NO can be converted into water-soluble NO2, a gas conveying tube of the reaction column is arranged around the inner wall of a reaction cavity, a plurality of gas outlets are formed in the surface of the gas conveying tube, and due to the design, the ozonecan be sufficiently mixed with the smoke, and the reaction efficiency can be improved; a stirring shaft driven by a motor is arranged inside the cleaning tank, a cleaning liquid can be stirred, the smoke fed into the cleaning tank can be rapidly dissolved in the cleaning liquid, and the consequences that the cleaning liquid is low in flowability, saturated in single area and not easy to dissolvecan be avoided.