The invention discloses a high-efficiency atomization desulfurization device which comprises a lime powder loading and storage system, a lime slurry preparation system, a lime slurry transfer system,a lime slurry storage system, a lime slurry injection system, a desulfurization catalyst storage system and a desulfurization catalyst injection system. The outlet of the lime powder loading and storage system is connected with the inlet of the lime slurry preparation system; the outlet of the lime slurry preparation system is connected with the inlet of the lime slurry storage system through thelime slurry transfer system. The outlet of the lime slurry storage system is connected with the inlet of the lime slurry injection system through the lime slurry transfer system; the outlet of the desulfurization catalyst storage system is connected with the inlet of the desulfurization catalyst injection system. In addition, the invention also discloses a high-efficiency atomization desulfurization method. The high-efficiency atomization desulfurization device has simple structure, low input, low cost, low energy consumption, and desulfurization efficiency of more than 95%; and SO3 is almostcompletely removed.