Gautreks saga is a Scandinavian legendary saga put to text towards the end of the 13th century which survives only in much later manuscripts. It seems to have been intended as a compilation of traditional stories, often humorous, about a legendary King Gautrek of West Geatland, to serve as a kind of prequel to the already existing Hrólfs saga Gautrekssonar. See also king of the Geats.

A legendary saga or fornaldarsaga is a Norse saga that, unlike the Icelanders' sagas, takes place before the settlement of Iceland. There are some exceptions, such as Yngvars saga víðförla, which takes place in the 11th century. The sagas were probably all written in Iceland, from about the middle of the 13th century to about 1400, although it is possible that some may be of a later date, such as Hrólfs saga kraka.