GRS
- GRS Riflestocks
- Gabungan Rakyat Sabah
- Gamma Ray Spectrometer (2001 Mars Odyssey)
- Gamma-ray spectrometer
- Gauche républicaine et socialiste
- Gender-affirming surgery
- General Railway Signal
- Genetic risk score
- Geneva Reformed Seminary
- Gifted Rating Scales
- Global Resource Serialization
- Global Response Staff
- Government Rubber-Styrene
- Grand Rapids Symphony
- Grassroot Soccer
- Graves Registration Service
- Great Red Spot
- Great River Charter Montessori School
- Gresi language
- Grosseto Air Base
- Guilford Rail System
- Parti Gagasan Rakyat Sabah
- The Gerry Ryan Show