BBO may stand for:
- Barium boron oxide, another name of barium borate
- Big Bang Observer, planned space gravitational wave observatory
- IATA code for Berbera Airport
- "BBO (Bad Bitches Only)", a song by Migos from the album Culture II
- Beta barium borate (β-BaB2O4) crystal
- Bundesbahn Österreich, a former name for the Austrian Federal Railways
- Bureau Bijzondere Opdrachten, a WWII Dutch secret service
- Bridge Base Online, for the game of bridge
- British Ballet Organization
- BBO, the ICAO code for Flybaboo