| Pahau River | |
| Source1 Location: | Tekoa Range |
| Mouth Location: | Hurunui River |
| Subdivision Type1: | Country |
| Subdivision Name1: | New Zealand |
| Length: | 40km (30miles) |
The Pahau River or Pahu River is a river of the north Canterbury region of New Zealand's South Island. It has its origins in the Tekoa Range, 25km (16miles) northwest of Culverden, and flows initially north before turning south to flow down a long valley between two ridges. At the northern edge of the Canterbury Plains it turns southeast, flowing past the southern outskirts of Culverden to reach the Hurunui River 8km (05miles) southeast of the town.