GTC may stand for:
- Gain time control
- Gas Turbine Centre (Sweden)
- General Teaching Council (several UK)
- General Technology Corporation
- Genome Therapeutics Corporation
- Gopher Tortoise Council
- Gran Telescopio Canarias
- Green tea catechins
- Ground tactical commander
- Grove Theater Center (Garden Grove, California, gtc.org)
- Gateway Technical College (Wisconsin, gtc.edu)
- Greenville Technical College (Greenville, South Carolina)
- Griffin Technical College
- Gwinnett Technical College
- GTC Telecom