CGB may refer to:
- covertgoBlue, a popular youtube content creator
- Chorionic gonadotropin beta, a protein encoded by the CGB gene
- Christian Trade Union Federation of Germany
- Compagnie des Chemins de Fer de Grande Banlieue, a defunct railway in France
- Consumer & Governmental Affairs Bureau, a part of the Federal Communications Commission
- Craigieburn railway station, Melbourne
- Game Boy Color (product code CGB-001), Nintendo
- Marechal Rondon International Airport (IATA code), in Cuiabá, Brazil
- Station code for Cigombong railway station