GBW is a three-letter acronym that could refer to:
- Green Bay and Western Railroad
- Glowing Brightwood Staff
- Gain-bandwidth product (GB or GBW), product of amplifier midband gain and bandwidth (e.g., unity-gain frequency of frequency compensated operational amplifiers)
- Ground Breaking Wrestling, a hardcore wrestling promotion
- The Guild of Bookworkers, a bookbinding organization in the United States.
- Galvanized before weaving