GG, Gg, or gg may mean:
History and science
- General Government, the name given by Germany to the governing authority in Poland after its occupation by the Wehrmacht in 1939
- Governor-General, the viceroy of many Commonwealth Realms
- Grundgesetz, the German constitution
- Gigagram, an SI unit of mass equal to 1,000,000 kilograms
Business
- GG, the IATA airline designator for Air Comores International
- .gg, the Top-Level Domain country code for Guernsey
- GarageGames, an internet game publisher
- Game Gear, a handheld gaming console
- Gadu-Gadu, an instant messaging program popular in Poland
- Gucci's monogram symbol
- Guilty Gear, a video game
Slang and popular culture
- General Grievous, a Star Wars character
- Gilmore Girls, a television comedy
- Golden Girls, a television sitcom
- Good Game, a television show for gamers
- GG, used in personal ads to refer to a "Genetic Girl" or "Real Girl", as opposed to a transvestite, transsexual, or transgendered (male-to-female) girl
- *gg*, German slang for *grinsgrins*
- A slang term for a horse
- An abbreviation for G.G. Allin
- "good game" or rarely, "great game"
- "good going", used sarcastically
- "good God"
- "grin grin"
- "giggles" in Ragnarok Online
- "godly gear" or a phrase for a godly feat in Diablo 2
- "grinsgrins"
- "Guilty Gear", A 2D fighting game.
- "Get Going"