| Acronym | Definition |
|---|
| NII | National Institute of Informatics (Japan) |
| NII | National Information Infrastructure |
| NII | Nuclear Installations Inspectorate |
| NII | Net Interest Income |
| NII | Networks and Information Integration |
| NII | National Institute of Informatics |
| NII | National Institute of Immunology (New Delhi, India) |
| NII | Net Investment Income |
| NII | National Insurance Institute (Israel) |
| NII | Negara Islam Indonesia |
| NII | National Innovation Initiative |
| NII | Non Intrusive Inspection |
| NII | Network Intelligence India Pvt Ltd |
| NII | Non-Intrusive Imaging (security) |
| NII | National Investment Institute (Australia) |
| NII | Negative Impedance Inverter (electrical engineering) |
| NII | Non Intrusive Instrumentation (research; various organizations) |
| NII | National Implementation Issue |
| NII | Non-Ideal Interleaving |
| NII | National Informatization Index (South Korea) |
| NII | National Immigration Institute |
| NII | National Income Inquiry |