Ormurin Langi ("The Long Serpent") is a Faroese folk ballad. It was written in ca. 1830 by Jens Christian Djurhuus.
Written in 86 verses in Faroese, the song deals with the Norwegian king Olaf Tryggvason. The title Ormurin Langi refers to Olaf Tryggvason's ship with the same name (Ormrinn Langi in Old Norse).