The Topuni River is a river of the Northland Region of New Zealand's North Island. It flows generally south, with most of its length being through a drowned valley in the northeast of the Kaipara Harbour system. The Topuni River reaches the Oruawharo River — an arm of the Kaipara — 10 kilometres northwest of Wellsford.
"Place Name Detail: Topuni River". New Zealand Geographic Placenames Database. Land Information New Zealand. Retrieved 12 July 2009.
Coordinates: 36°15′S 174°28′E / 36.250°S 174.467°E