| Acronym | Definition |
|---|
| MGS | Metal Gear Solid |
| MGS | Ministry of Government Services (Ontario, Canada) |
| MGS | Mars Global Surveyor |
| MGS | Microsoft Game Studios |
| MGS | Manitoba Genealogical Society (Canada) |
| MGS | Machine Gun System |
| MGS | Master Gunnery Sergeant (USMC) |
| MGS | Movimento Giovanile Salesiano (Italian youth movement) |
| MGS | Magnetschwebebahn (German: Magnetic Hovercraft Railway) |
| MGS | Malaysian Government Securities |
| MGS | Modified Gram-Schmidt (algorithm) |
| MGS | Manchester Grammar School |
| MGS | Magnesium Sulfide |
| MGS | Magic Game Station |
| MGS | Media Gateway Server |
| MGS | Media Gateway Switch |
| MGS | Mud Gas Separator (oil engineering) |
| MGS | Marine Geophysical Survey |
| MGS | Maryland Geological Survey |
| MGS | Minnesota Geological Survey |
| MGS | Middleton Grange School (New Zealand) |
| MGS | Maidstone Grammar School (UK) |
| MGS | Methodist Girls' School (Singapore) |
| MGS | Monster Government Solutions (work staffing) |
| MGS | Matching Grant Scheme (various organizations) |
| MGS | Melbourne Grammar School (Victoria, Australia) |
| MGS | Mobile Ground System (US DoD) |
| MGS | Missile Guidance Set |
| MGS | Molecular Genetics of Schizophrenia |
| MGS | Master of Gerontological Studies (Miami University; Ohio) |
| MGS | Mediterranean Garden Society |
| MGS | Metallurgical Grade Silicon |
| MGS | Medical Gas Services (Phoenix, AZ) |
| MGS | Meckel-Gruber Syndrome |
| MGS | McMurdo Ground Station |
| MGS | Modern Grid Strategy |
| MGS | Mutation Generation System (Finnzymes Oy; Finland) |
| MGS | Mild Grade Steel |
| MGS | Mobile Ground Station |
| MGS | Mentone Grammar School (Melbourne, Australia) |
| MGS | Minnesota Gerontological Society (Saint Paul, MN) |
| MGS | Mission Ground Station |
| MGS | Medium Grade Service |
| MGS | Marriott Global Source |
| MGS | Microsoft Global Summit |
| MGS | Miscellaneous General Service |
| MGS | Mayo Graduate School of Medicine |
| MGS | Marine Graphics System |
| MGS | Mobile Guns System |
| MGS | Mat Ground Surfacing |
| MGS | Mobile GIS System |
| MGS | Multimedia Graphic Solutions |
| MGS | Micro-Gyroscopic System |
| MGS | Mitsubishi Generator Set |