| Otahu River | |
| Mouth Location: | Bay of Plenty |
| Subdivision Type1: | Country |
| Subdivision Name1: | New Zealand |
| Length: | 18abbr=onNaNabbr=on |
The Otahu River is a river of the Coromandel Peninsula, in the Waikato Region of New Zealand's North Island. It flows generally northeast from several streams with watersheds in the Coromandel Range, most notably the Wharekirauponga Stream. The Otahu reaches the sea immediately to the south of the town of Whangamatā.
The New Zealand Ministry for Culture and Heritage gives a translation of "place of Tahu [a personal name]" for Ōtahu.[1]