The Hoopoe ( /ˈhuːpuː/) (Upupa epops) is a colourful bird that is found across Afro-Eurasia, notable for its distinctive 'crown' of feathers. It is the only extant species in the family Upupidae. One insular species, the Giant Hoopoe of Saint Helena, is extinct, and the Madagascar subspecies of the Hoopoe is sometimes elevated to a full species. Like the Latin name upupa, the English name is an onomatopoetic form which imitates the cry of the bird.

The Hoopoe is classified in the Coraciiformes clade, a group that also includes kingfishers, bee-eaters, rollers, and woodhoopoes (forming a clade with this one according to Hackett et al. (2008)). A close relationship between the Hoopoe and the woodhoopoes is also supported by the shared and unique nature of their stapes. In the Sibley-Ahlquist taxonomy, the Hoopoe is separated from the Coraciiformes as a separate order, the Upupiformes. Some authorities place the woodhoopoes in the Upupiformes as well.

The fossil record of the hoopoes is very incomplete, with the earliest fossil coming from the Quaternary. The fossil record of their relatives is older, with fossil woodhoopoes dating back to the Miocene and those of an extinct related family, the Messelirrisoridae, dating from the Eocene.