| Wainuioru River | |
| Subdivision Type1: | Country |
| Length: | 46km (29miles) |
The Wainuioru River is a river of the Wellington Region of New Zealand's North Island. A major tributary of the Pahaoa River, it follows a twisting generally southwestward course from its origins 25 kilometres east of Masterton, reaching the Pahaoa 20km (10miles) southeast of Martinborough.