Aconitum uncinatum L. (Ranunculaceae) is reported for the first time for the state of Ohio. It grows in a mesic cove on the unglaciated Appalachian Plateau of Hocking County. The Ohio plants belong to the typical subspecies of A. uncinatum. The habitat is described and population specifics given. Aconitum uncinatum is officially listed as Endangered under Ohio law.