The invention discloses a high-efficiency flue gas spray drying desulfurization device, which includes a gas flow meter, a flue gas inlet pipe, an absorption tower, a filter plate, an electrostatic precipitator, a cyclone separator, a heater, a double reverse cone separator, and an atomization device , spraying, pump, feeding pipe and slaked lime tank, the flue gas inlet pipe is connected to the bottom of the absorption tower, the absorption tower is provided with a cyclone separator, the inner wall of the absorption tower is provided with a heater, and the lower part of the cyclone separator is installed obliquely. There is a filter plate, the top of the absorption tower is equipped with an exhaust pipe, one end of the return pipe is connected to the exhaust pipe, the other end of the return pipe is connected to the flue gas inlet pipe, the lowest end of the filter plate is connected to the electrostatic precipitator, and the outlet end of the electrostatic precipitator is connected to the slaked lime Tank connection, the bottom of the slaked lime tank is provided with a feed pipe, the pump and atomization device are installed on the feed pipe, the outlet of the feed pipe is provided with a spray discharge, and the inner wall of the top of the absorption tower is provided with a double reverse cone separator. The invention has the advantages of simple structure, convenient use, low cost and favorable promotion.