F. Andrieu (fl. late 14th century; possibly François or Franciscus Andrieu) was a French composer in the ars nova style of late medieval music. Nothing is known for certain about him except that he wrote Armes, amours/O flour des flours (Weapons, loves/O flower of flowers), a double ballade déploration, for the death of Guillaume de Machaut in 1377. The work has been widely praised and analyzed; it is notable for being one of two extant medieval double ballades for four voices, the only known contemporary musical setting of Eustache Deschamps and the earliest representative of the longstanding medieval and Renaissance lamentation tradition between composers. He may be the same person as Magister Franciscus, although the scholarly consensus on this identification is unclear. With P. des Molins, Jehan Vaillant and Grimace, Andrieu was one of the "post-Machaut" generation whose pieces retain enough ars nova qualities to be differentiated from composers of ars subtilior.