ISOI
| Acronym | Definition |
|---|---|
| ISOI | International School of Islamabad (Pakistan) |
| ISOI | Instrument Society of India (est. 1970) |
| ISOI | Istituto Sull Orticoltura Industriale (Italian: Horticulture Industry Institute; Bari, Italy) |
| ISOI | Internet Security and Operational Intelligence |