The name Ragnhild Sigurdsdotter may refer to two different figures from Old Norse literature, an amalgam of them, or a purely fictitious figure.
- The wife of Halfdan the Black (c. 810 – c. 860)
- A woman who lived during the late 9th and/or early 10th centuries, who was the daughter of Sigurd Hart of the Dagling clan.
While some traditional accounts portray these two figures as the same woman, they (and their relatives) lived in differing periods.
Some accounts describe her as the daughter of Sigurd Snake-in-the-Eye and others as his granddaughter.