TCA may refer to:

In chemistry:

• Trichloroethane, organochloride solvent
• Trichloroacetic acid, chemical used to precipitate protein in serum
• TCA, an abbreviation for tricyclic antidepressant, a class of anti-depressant drugs
• TCA, or 2,4,6-trichloroanisole, a chemical compound which is the cause of cork taint in wine
• TCA cycle or citric acid cycle

In associations:

• Television Critics Association
• Total Community Action
• Trans-Canada Air Lines
• Taiwanese Cultural Association
• Train Collectors Association
• Trinity Christian Academy

In other uses:

• Advanced Telecommunications Computing Architecture, a specification set for carrier grade communications equipment
• Terminal Control Area, a volume of controlled airspace
• Teen Choice Awards