AGC is a three-letter abbreviation that may refer to:
- Associations
- Associated General Contractors of America, association of commercial construction contractors
- Apostolic Generation Church, a non-denominational church located in Jakarta, Indonesia
- Associated Gospel Churches of Canada, Canadian evangelical Christian denomination
- Assyrian General Conference, political organization representing Assyrians in Iraq.
- Australian Girls Choir, choir; part of the Australian School of Performing Arts
- Companies
- Australian Guarantee Corporation, financial company
- American Greetings Corporation. greetings card company
- Asahi Glass Co., Ltd., technical glass manufacturing company
- Military
- Auxiliary General Communications Vessel, a U.S. Navy ship class, of type Amphibious Command
- Army Geospatial Center, formerly the Topographic Engineering Center, and part of the US Army Corps of Engineers
- Adjutant General's Corps
- Science and technology
- Active galactic core
- Apollo Guidance Computer
- Atypical Glandular Cells, in the Bethesda System for reporting for Pap smear results
- Automatic gain control, automatic control of electronic amplification level
- Automatic generation control, automatic control of electricity generating powerplants
- Automotive glass case, a kind of fuse (automotive)
- Other
- Allegheny County Airport (IATA airport code AGC), an airport in West Mifflin, Pennsylvania
- Autorail à Grande Capacité, a type of train