The genus Bubo was introduced in 1805 by the French zoologist André Duméril for the horned owls.

[3] The word bubo is Latin for the Eurasian eagle owl and was used as the specific epithet for the species by Carl Linnaeus in 1758.

[5][6] The genus contains 10 extant species:[6] Sometimes included in this genus: Named and distinct Bubo species are: Some notable undescribed fossils of prehistoric horned owls, usually quite fragmentary remains, have also been recorded: Specimen UMMP V31030, a Late Pliocene coracoid from the Rexroad Formation of Kansas (U.S.), cannot be conclusively assigned to either Bubo or Strix.

"Bubo" poirreiri from the Late Oligocene or Early Miocene of Saint-Gérard-le-Puy in France, is now placed in Mioglaux.

On the other hand, the supposed fossil heron "Ardea" lignitum from the Late Pliocene of Plaue-Rippersroda (Germany) was apparently an owl and close to Bubo or more probably actually belongs here.