LSN may refer to:
- Laser Squad Nemesis, a turn-based strategy game by Codo Technologies.
- Learning and Skills Network, a UK organisation delivering quality improvement and staff development programmes in the skills and education sector.
- Lenguaje de Signos Nicaragüense, a pidgin form of Nicaraguan Sign Language.
- Livingston North railway station, Scotland; National Rail station code LSN.
- The IATA location identifier for Los Banos Municipal Airport.
- Life Starts Now, an album by Three Days Grace.
- Log sequence number, a concept used for database recovery.
- Large Scale NAT, an approach to IPv4 network design where end sites are configured with private network addresses
- Lymphoedema Support Network, a UK lymphoedema charity organisation.
- Legal Scholarship Network, a US based legal research publication and indexing service, under SSRN.