- Japanese French Laboratory for Informatics
- Japan Science and Technology Agency
- Jet Propulsion Laboratory
- JEUMONT Electric
- Jeumont Electric, Altawest
- JEUMONT ELETRIC
- Jeunes Équipes de l'Institut de Physique du Collège de France
- Johann Radon Institute for Computational and Applied Mathematics
- John P. Hussman Institute for Human Genomics
- Joint Center for Structural Genomics
- Joint Japanese-French Robotics Research Laboratory [Japon]