| Tīnui River | |
| Mouth Location: | Whareama River |
| Subdivision Type1: | Country |
| Subdivision Name1: | New Zealand |
| Length: | 16abbr=onNaNabbr=on |
The Tīnui River is a river of the Wellington Region of New Zealand's North Island. It flows initially east from its origins in the northern Wairarapa before turning southwest to flow parallel with the Pacific coast. It reaches the Whareama River at the settlement of Tīnui, 30km (20miles) east of Masterton.