G
- GAF, Government Aircraft Factories – Australia, (1941–1987) > Aerospace Technologies of Australia
- Gannet, Gannet Aircraft – United States
- Ganzavia, Ganzavia Kft – Hungary
- Gardan, Avions Yves Gardan – France (see Constructions Aéronautiques du Béarn)
- Garland, The Garland Aircraft Company – United Kingdom
- Garland Aerospace, Camden, New South Wales, Australia
- Garrison, Peter Garrison – United States
- Gastambide-Mengin, Gastambide-Mengin – France
- Gatard, Avions A. Gatard – France
- Gatard, Société des Avions Statoplan, A. Gatard – France
- Gates Learjet, Gates Learjet Corporation – United States
- Gavilan, El Gavilán SA – Colombia
- GEFA-FLUG GmbH, Gesellschaft zur Entwicklung und Förderung Aerostatischer Flugsysteme GmbH – Germany, (1975–present)
- Gemini Powered Parachutes, Culver, Indiana, United States
- Genair, Genair – South Africa
- General Aircraft, General Aircraft Corporation – United States
- General Aircraft Limited, General Aircraft Ltd – United Kingdom, (1931–1948) (GAL) > Blackburn and General Aircraft
- General Atomics, General Atomics – United States
- General Avia, General Avia Costruzioni Aeronautiche SRL – Italy
- General Aviation Design Bureau of Ukraine – Kiev, Ukraine
- General Dynamics, General Dynamics Corporation – United States
- General Motors, Eastern Aircraft Division of General Motors Corporation – United States
- German Bianco, German Bianco SA, Fabrica Argentina de Aerodinos – Argentina
- Giles, Richard Giles – United States
- Gin Gliders, Yongin, South Korea
- Gippsland, Mahindra Aerospace India – Australia
- Giravia, Giravia – France
- Glaser-Dirks, Glaser-Dirks Flugzeugbau GmbH – Germany
- Glasflügel – Germany
- Glass, Glass Aircraft de Colombia – Colombia
- Glassic, Glassic Composites LLC – United States
- Glendower Aircraft Company, Glendower Aircraft Company – United Kingdom
- Global, Global Helicopter Technology Inc – United States
- Globe, Globe Aircraft Corporation – United States
- Gloster Aircraft Company Ltd – United Kingdom, > Whitworth Gloster Aircraft Ltd. 1961 Hawker Siddeley Group
- Gloucestershire Aircraft, Gloucestershire Aircraft Co. – United Kingdom, > Gloster 1926
- Głowiński, Bronisław Głowiński – Poland
- Goair, Goair Products – Australia
- Golden Circle, Golden Circle Air Inc – United States
- Gomolzig, Herbert Gomolzig Ingenieurbüro – Germany
- Goodrich, Goodrich Corporation – Headquarters North Carolina – United States
- Goodyear, Goodyear Aircraft Corporation – United States
- Gothaer Waggonfabrik, Gothaer Waggonfabrik – Germany, (GWF)
- Gourdou-Leseurre, Gourdou-Leseurre – France
- Government Aircraft Factory, Government Aircraft Factory – Finland
- Gradient sro, Prague, Czech Republic
- Grahame-White, Grahame-White Aviation Co. Ltd. – United Kingdom, (Claude Grahame-White)
- Granville Brothers Aircraft, Granville Brothers Aircraft – United States
- Great Lakes, Great Lakes Aircraft Company Inc – United States
- Great Lakes, Great Lakes Aircraft Corporation – United States
- Great Lakes, Great Lakes Aircraft Inc – United States
- Great Plains, Great Plains Aircraft Supply Company Inc – United States
- Green Sky Adventures, Hawthorne, Florida, United States
- Grega, John W. Grega – United States (see Pietenpol Air Camper)
- Grémont, Grémont – France
- Griffon, Griffon Aerospace Inc – United States
- Grinvalds, Jean Grinvalds – France
- Grob, Burkhart Grob Flugzeugbau GmbH & Co kg – Germany
- Groen, Groen Brothers Aviation Inc – United States
- Grosso, Grosso Aircraft Inc – United States
- Grove, Grove Aircraft Company – United States
- Grover, Grover Aircraft Corporation – United States
- Grumman, Grumman Aircraft Engineering Corporation – United States
- Grumman, Grumman Corporation – United States, (1930–1994)
- Grumman American, Grumman American Aviation Corporation – United States
- Guizhou, Guizhou Aviation Industrial Corporation – China
- Gulfstream Aerospace, Gulfstream Aerospace Corporation – United States, (1978–present)
- Gulfstream American, Gulfstream American Corporation – United States
- Gyro-Kopp-Ters, Lake City Florida, United States
- Gyroflug, Gyroflug Ingenieursgesellschaft mbH – Germany