FSE may refer to:
Federation of European Scouting (disambiguation) (French: Fédération du Scoutisme Européen)
Ferrovie del Sud Est, an Italian railway company
Football Supporters Europe, a football fan network
Fung Seng Enterprises, a Hong Kong conglomerate
Franciscan Sisters of the Eucharist, a Roman Catholic religious congregation
Fast Software Encryption, a cryptography conference
Frankfurt Stock Exchange, Germany's largest stock exchange
Fukuoka Stock Exchange, a stock exchange in Japan
Feline spongiform encephalopathy
Fetal scalp electrode
Fast Spin Echo, a type of magnetic resonance imaging sequence
Free surface effect, liquids in slack tanks
Finnish Sign Language (fse), the ISO languagecode for the Finnish sign language
Fremont Street Experience, a pedestrian mall
'service