"Guigemar" is a Breton lai, a type of narrative poem, written by Marie de France during the 12th century. The poem belongs to the collection known as The Lais of Marie de France. Like the other lais in the collection, Guigemar is written in the Anglo-Norman language, a dialect of Old French, in rhyming octosyllabic couplets.
"Guigemar" is one of the works in which the author explicitly gives her name as "Marie." In the prologue of this lai, she proclaims two goals for her work: to give rightful praise to people who have earned it, despite what envious rivals may have said; and to present the stories behind certain songs that were well-known at the time. It has been suggested that the prologue to "Guigemar" predates the overall prologue to the Lais in the Harley 978 manuscript, the only manuscript that records all twelve of Marie's known lais.