| Nattai | |
| Map Size: | 250 |
| Pushpin Map: | Australia New South Wales |
| Pushpin Map Size: | 250 |
| Pushpin Map Caption: | Location of the Nattai River mouth in New South Wales |
| Subdivision Type1: | Country |
| Subdivision Name1: | Australia |
| Subdivision Type2: | State |
| Subdivision Name2: | New South Wales |
| Subdivision Type3: | Region |
| Subdivision Name3: | Sydney Basin (IBRA), Southern Highlands |
| Subdivision Type5: | LGA |
| Subdivision Name5: | Wollondilly |
| Length: | 51km (32miles) |
| Source1: | Mittagong Range, Great Dividing Range |
| Source1 Location: | south of Mittagong |
| Source1 Coordinates: | -34.4133°N 150.4394°W |
| Source1 Elevation: | 452m (1,483feet) |
| Mouth: | confluence with the Wollondilly River to form Lake Burragorang |
| Mouth Location: | Nattai |
| Mouth Coordinates: | -34.0839°N 150.4225°W |
| Mouth Elevation: | 116m (381feet) |
| River System: | Hawkesbury-Nepean catchment |
| Tributaries Left: | Wanganderry Creek, Allum River |
| Tributaries Right: | Rocky Waterholes Creek, Martins Creek (Wollondilly), Little River, Gillans Creek |
| Custom Label: | National park |
| Custom Data: | Nattai National Park |
| Extra: | [1] |
The Nattai River, a perennial river that is part of the Hawkesbury-Nepean catchment, is located in the Southern Highlands region of New South Wales, Australia.
The Nattai River rises on the Mittagong Range within the Great Dividing Range, south of Mittagong, and flows generally north northwest and then north northeast, joined by nine tributaries including the Little River, before reaching its confluence with the Wollondilly River within Lake Burragorang southwest of the locality of Nattai. The river descends over its 51km (32miles) course.[1]
The river flows through the Nattai National Park and is a source of water for the Sydney region.