HN may refer to:
- Hacker News, a popular tech news site
- Hanoi, Vietnam
- Hawk Nelson, a Christian punk band
- Heavylift Cargo Airlines' IATA airline designator
- Herceg Novi, a town in Montenegro
- Heilbronn, a city in Germany
- Honduras' ISO 3166-1 alpha-2 country code
- Honduras Country code top-level domain .hn
- Host nation, in connection with counter-insurgency operations
- Hutchinson and Northern Railway
- Hyperdimension Neptunia, a game
- HN, the abbreviation for Hospitalman, a United States Navy Hospital Corpsman rate
- HN, a numbering system for Royal Doulton Figurines named after employee Harry Nixon
- Hn., or Hanım, a Turkish word for Mrs.
- Hn., an abbreviation for Horn (instrument) in musical scores
- Hardware Node, Virtual Ethernet device concept