GB3 may refer to:

• Globotriaosylceramide - It is also known as CD77, Gb3, and ceramide trihexoside.
• Greater Brisbane League - formerly Greater Brisbane Base Ball Board, an Australian baseball league
• Ghostbusters 3, a potential film in the Ghostbusters franchise
• GB3, a solo music project by Australian performer Glenn Bennie

• Sumbe
• Sumber
• Sumbiling
• Sumbing
• Sumbitch
• Sumbl
• Sumbu Kalambay
• Sumbu kalambay
• Sumbul
• Sumbu National Park
• Sumburgh
• Sumbwa people
• Sumeba Miyako no Cosmos-sō Suttoko Taisen Dokkoider
• Sumed
• Sumedang
• Sumedang Regency
• Sumedha Karmahe
• Sumedha Karmak
• Sumedho
• Sumed pipeline
• Sumeg
• Sumegpraga
• Sumel
• Sumela
• Sum Elai-Mang