In Greek mythology, the Hyperboreans (Ancient Greek: ὑπερβόρε(ι)οι, romanized: hyperbóre(i)oi, pronounced [hyperbóre(ː)oi̯]; Latin: Hyperborei) were a mythical people who lived in the far northern part of the known world. Their name appears to derive from the Greek ὑπέρ Βορέᾱ, "beyond Boreas" (the god of the north wind). Some scholars prefer a derivation from ὑπερφέρω (hyperpherō, "to carry over").

Despite their location in an otherwise frigid part of the world, the Hyperboreans were believed to inhabit a sunny, temperate, and divinely blessed land. In many versions of the story, they lived north of the Riphean Mountains, which shielded them from the effects of the cold north wind. The oldest myths portray them as the favorites of Apollo, and some ancient Greek writers regarded the Hyperboreans as the mythical founders of Apollo's shrines at Delos and Delphi.

Later writers disagreed on the existence and location of the Hyperboreans, with some regarding them as purely mythological, and others connecting them to real-world peoples and places in northern Eurasia (e.g. Britain, Scandinavia, or Siberia). In medieval and Renaissance literature, the Hyperboreans came to signify remoteness and exoticism. Modern scholars consider the Hyperborean myth to be an amalgam of ideas from ancient utopianism, "edge of the earth" stories, the cult of Apollo, and exaggerated reports of phenomena in northern Europe (e.g. the Arctic "midnight sun").

The earliest extant source that mentions Hyperborea in detail, Herodotus' Histories (Book IV, Chapters 32–36), dates from c. 450 BC. Herodotus recorded three earlier sources that supposedly mentioned the Hyperboreans, including Hesiod and Homer, the latter purportedly having written of Hyperborea in his lost work Epigoni. Herodotus voices doubts as to the attribution of the work to Homer.

Herodotus wrote that the 7th-century BC poet Aristeas wrote of the Hyperboreans in a poem (now lost) called Arimaspea about a journey to the Issedones, who are estimated to have lived in the Kazakh Steppe. Beyond these lived the one-eyed Arimaspians, further on the gold-guarding griffins, and beyond these the Hyperboreans. Herodotus assumed that Hyperborea lay somewhere in Northeast Asia.

Pindar, lyric poet from Thebes and a contemporary of Herodotus in the tenth Pythian Ode described the Hyperboreans and tells of Perseus's journey to them.

Other 5th-century BC Greek authors, such as Simonides of Ceos and Hellanicus of Lesbos, described or referenced the Hyperboreans in their works.

The Hyperboreans were believed to live beyond the snowy Riphean Mountains, with Pausanias describing the location as "The land of the Hyperboreans, men living beyond the home of Boreas." Homer placed Boreas in Thrace, and therefore Hyperborea was in his opinion north of Thrace, in Dacia. Sophocles (Antigone, 980–987), Aeschylus (Agamemnon, 193; 651), Simonides of Ceos (Schol. on Apollonius Rhodius, 1. 121) and Callimachus (Delian, [IV] 65) also placed Boreas in Thrace.