Longnon
Longnon is a family name that may refer to:
- Auguste Longnon (1844–1911), French historian, Romanist, Medievalist and toponomist
- Guy Longnon (1924–2014), French jazz trumpeter and music teacher
- Henri Longnon (1882–1964), French Romanist, Italianist, archivist and translator
- Jean-Loup Longnon (* 1953), French jazz trumpeter and composer