| Acronym | Definition |
|---|
| JSI | John Snow, Inc (Boston, MA) |
| JSI | Jozef Stefan Institute (est. 1949; Slovenia) |
| JSI | Journal of School Improvement |
| JSI | Journal of Social Issues |
| JSI | Judicial Studies Institute (Dublin, Ireland) |
| JSI | Jantzi Social Index (Michael Jantzi Research Associates) |
| JSI | Japan Securities Incorporated (Vietnam) |
| JSI | Japanese Society for Immunology (Tokyo, Japan) |
| JSI | Skiathos, Greece - Skiathos (Airport Code) |
| JSI | Japanese Standards Association |
| JSI | Japan Spirit Importation (French automobile club) |
| JSI | JCALS (Joint Computer-Aided Acquisition and Logistics Support) Standard Interface |
| JSI | Julian Street Inn (San Jose, CA homeless shelter) |
| JSI | Joint Surface Index |
| JSI | Joint Support Item |
| JSI | Java Services Infrastructure |
| JSI | Jaclyn Smith International |
| JSI | Journal of Stomatological Investigation (oral medicine) |