This is a list of mammals of the Northern Territory of Australia:
The following tags are used to highlight each species' conservation status as assessed by the International Union for Conservation of Nature:
| EX | Extinct | No reasonable doubt that the last individual has died. | |
| EW | Extinct in the wild | Known only to survive in captivity or as a naturalized populations well outside its previous range. | |
| CR | Critically endangered | The species is in imminent risk of extinction in the wild. | |
| EN | Endangered | The species is facing an extremely high risk of extinction in the wild. | |
| VU | Vulnerable | The species is facing a high risk of extinction in the wild. | |
| NT | Near threatened | The species does not meet any of the criteria that would categorise it as risking extinction but it is likely to do so in the future. | |
| LC | Least concern | There are no current identifiable risks to the species. | |
| DD | Data deficient | There is inadequate information to make an assessment of the risks to this species. |
Some species were assessed using an earlier set of criteria. Species assessed using this system have the following instead of near threatened and least concern categories:
| LR/cd | Lower risk/conservation dependent | Species which were the focus of conservation programmes and may have moved into a higher risk category if that programme was discontinued. | |
| LR/nt | Lower risk/near threatened | Species which are close to being classified as vulnerable but are not the subject of conservation programmes. | |
| LR/lc | Lower risk/least concern | Species for which there are no identifiable risks. |