In Norse mythology, Þrymr (Thrymr, Thrym; "uproar") was king of the jǫtnar. In one legend, he stole Mjǫlnir, Thor's hammer, to extort the gods into giving him Freyja as his wife. His kingdom was called Jötunheimr, but according to Hversu Noregr byggðist, it was the Swedish province Värmland, then a part of Norway.
Þrymr was foiled in his scheme by the gracefulness of Heimdallr, the cunning of Loki, and the sheer violence of Thor, who later killed Þrymr, his sister, and all of the jotnar kin that had been present at the wedding reception. The poem Þrymskviða gives the details of how Thor got his hammer back. Bergfinnr is a son of Þrymr.