MTG may stand for:
- Magic: The Gathering, a collectible card game made by Wizards of the Coast.
- Modern Times Group, a Swedish media company and owner of Viasat and Metro International.
- Methanol to gasoline, a process for producing liquid hydrocarbons from methanol.
- Maria-Theresia-Gymnasium, a Munich school for gifted students.
- Metro Tunneling Group, joint venture of Five Companies.
- Microturbine Generator
- Middle temporal gyrus, a region in the brain
- Meteosat Third Generation, the next generation of geostationary meteorological satellites built for EUMETSAT.
Mtg is also used as an abbreviation for the words "meeting" and "mortgage".