| Wonboyn River | |
| Name Other: | Narrabarba Creek |
| Subdivision Type1: | Country |
| Subdivision Name1: | Australia |
| Subdivision Type2: | State |
| Subdivision Name2: | New South Wales |
| Subdivision Type3: | Region |
| Subdivision Name3: | South East Corner (IBRA), South Coast |
| Subdivision Type5: | Local government area |
| Subdivision Name5: | Bega Valley |
| Length: | 18km (11miles) |
| Depth Avg: | 2.7m (08.9feet) |
| Source1: | Narrabarba Creek and Watergums Creek |
| Source1 Elevation: | 44m (144feet) |
| Mouth: | Tasman Sea, South Pacific Ocean |
| Mouth Location: | Disaster Bay, near Green Cape |
| Basin Size: | 335km2 |
| Tributaries Left: | Stevens Creek |
| Extra: | [1] [2] |
The Wonboyn River, an open youthful wave dominated barrier estuary[2] or perennial stream, is located in the South Coast region of New South Wales, Australia.
Wonboyn River is formed by the confluence of Narrabarba Creek and Watergums Creek, within Beowa National Park, east of the Princes Highway and southeast of the locality of Kiah, approximately north of Timbillica Hill. The river flows generally east, northeast, and then southeast, joined by one minor tributary, flowing through Wonboyn Lake, before reaching its mouth within Disaster Bay, at the Tasman Sea of the South Pacific Ocean southeast of Green Cape. The river descends over its course.[1]
The catchment area of the river is with a volume of over a surface area of, at an average depth of .[3]