The Mangatewainui River is a river of the Manawatū-Whanganui region of New Zealand's North Island.

An upper tributary of the Manawatu River, it flows generally southeast from its sources in the Ruahine Range northwest of Norsewood, and meets the young Manawatu River 8 kilometres (5 mi) east of Dannevirke.

"Place name detail: Mangatewainui River".

Land Information New Zealand.

This article about a river in Manawatū-Whanganui is a stub.