LFN may refer to:
- La Familia Network, a Spanish-language, family-oriented television network
- La Femme Nikita (TV series)
- Last Friday Night (T.G.I.F.), a 2011 single by Katy Perry
- Lingua Franca Nova, an auxiliary constructed language by C. George Boeree
- Long fat network, a description of certain data network connections
- Long filename, a FAT filename system introduced in Windows NT 3.5 and Windows 95