HMS is a TLA that may stand for:
- Her Majesty's Ship or His Majesty's Ship (Royal Navy)
- hour-minute-second
- Harvard Medical School
- Haslemere Musical Society
- Hazardous materials safety
- Headend management station
- Health monitoring system
- Heavy melting scrap
- Helmet-mounted sight
- Her Majesty's Service or His Majesty's Service
- Hidden Markov source
- Highly migratory species (fisheries)
- High Mountain Software (hms.com)
- High melting scrap
- Hind Mazdoor Sabha (India)
- Historical Maritime Society (hms.org.uk)
- Historical Metallurgy Society
- Holonic manufacturing system
- Home media server
- Hull mounted sonar
- Hybrid management sublayer
- Management systems:
- Handheld management system
- Harvesting management system
- Hazard management system
- Home management system
- Hospital management system
- Hotel management system
- Hypertext management system