FSE may refer to:
Organizations Federation of European Scouting (disambiguation) (French: ) 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
Computing Fast Software Encryption, cryptography conference Finite-state entropy, entropy coding scheme
Finance Frankfurt Stock Exchange, Germany's largest stock exchange Fukuoka Stock Exchange, a stock exchange in Japan
Human and veterinary medicine Feline spongiform encephalopathy Fetal scalp electrode
Science and technology Fast Spin Echo, a type of magnetic resonance imaging sequence Free surface effect, liquids in slack tanks
Other Finnish Sign Language (fse), the ISO languagecode for the Finnish sign language Fremont Street Experience, a pedestrian mall Field service engineer