| Postal River | |
| Pushpin Map: | New Zealand#New Zealand South Island |
| Pushpin Map Size: | 270px |
| Pushpin Map Caption: | Mouth of the Postal River |
| Source1: | Bald Knob |
| Source1 Coordinates: | -41.1661°N 172.274°W |
| Mouth Location: | Ōpārara River |
| Mouth Coordinates: | -41.1946°N 172.1902°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | New Zealand |
| Length: | 8km (05miles) |
| Progression: | Postal River → Ōpārara River → Karamea Bight → Tasman Sea |
| Tributaries Left: | Bovis Creek, New Chum Creek |
| Tributaries Right: | Castor Creek |
The Postal River is a river of the West Coast Region of New Zealand's South Island. It flows west from the Fenian Range, reaching the Ōpārara River five kilometres northeast of Karamea. The Postal River's entire length is within Kahurangi National Park.