JCA
- Camp JCA Shalom
- Jackie Chan Adventures
- Jain Center of America
- Japan Chess Association
- Japan Cricket Association
- Japanese Cancer Association
- Java Cryptography Architecture
- Java EE Connector Architecture
- Jean-Claude Ades
- Jewish Colonisation Association
- Joint Cargo Aircraft
- Joint Combat Aircraft
- Joint capability areas
- Joliet Catholic Academy
- Josephite Community Aid
- Journal of Computational Acoustics
- Journal of Contemporary Antisemitism
- Juvenile chronic arthritis