An atomizing disc, an atomizing device with the atomizing disc, and an unmanned aerial vehicle are provided. The atomizing disc includes: a bottom disc, an upper surface of the bottom disc being provided with a liquid inlet space; and a plurality of ribs, the plurality of ribs being disposed on the upper surface of the bottom disc and being spaced apart in a circumferential direction of the bottom disc. A centrifugal flow passage in communication with the liquid inlet space is defined between two adjacent ribs and the bottom disc. An end of a rib close to an edge of the bottom disc is provided with a first groove penetrating a side portion of the rib so as to cut fluid flowing through the centrifugal flow passage.