A fen is a type of wetland.

Fen, Fenn, Fens, Fenns, may also refer to:

People

• Fen (name), a Chinese given name and surname

• Fen Cresswell (1915–1966), New Zealand cricketer

• Fen McDonald (1891–1915), Australian rules footballer

• Kees Fens (1920–2008), Dutch writer

• Vitaly Fen (born ), Uzbekistani diplomat

Places

• Back Bay Fens, a park in Boston, Massachusetts

• The Fens, a low-lying geographical region of eastern England

• Fenns, Indiana, an unincorporated community

• Fen Complex, Norway, an area of unusual igneous rocks

• Fen Prefecture, a region of Imperial China

• Fen River, in China

• Fenn College, predecessor of Cleveland State University

• Fenn Tower, building on the campus of Cleveland State University

• Fenn's Moss, part of a British nature reserve

Chinese units of measurementChinese units of measurement

• Fen (currency), , a unit of the renminbi, the currency of China

• Fen (land), , a Chinese unit of land area

• Fen (length), , a Chinese unit of length

Other uses

• Fen (band), a British metal band

• Fen (play), a play by the British playwright Caryl Churchill

• Far East Network, a network of American military radio and television stations

• Federation of European Neuroscience Societies (FENS), a scholarly federation

• Fen TV, a Bulgarian television channel

• Fenny Stratford railway station, in England

• Fernando de Noronha Airport, in Brazil

• Festival of New Songs, a Slovenian music festival

• Final Exit Network (FEN), an American right-to-die advocacy group

• Flap endonuclease

• Forsyth–Edwards Notation (FEN) for chess positions

• Fédération des Étudiants Nationalistes (FEN), a defunct French far-right students' association

• Fen or three-legged turtle from Chinese mythology

• FAA Enterprise Network Services (FENS) of the Federal Aviation Administration