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