Gran
- Hada
- Granit
- Granit , Ragnar Arthur
- Green , George
- Gregor , William
- Gregory
- Gregory , James
- Griffin , Donald Redfield
- Griffith , Fred
- Grignard , François Auguste Victor
- Grimaldi , Francesco Maria
- Grisebach , August Heinrich Rudolph
- Guericke
- Guericke , Otto von
- Guettard , Jean Etienne
- Guillaume , Charles Edouard
- Guillemin
- Guillemin , Roger
- Guldberg , Cato Maximilian
- Guldberg, Cato Maximilian
- Gullstrand , Allvar
- Gutenberg , Beno
- Guth
- Guth , Alan Harvey
- Guyot , Arnold Henry
- Guyton de Morveau , Baron Louis Bernard
- Haber
- Haber , Fritz