The Topuni River is a river in the upper North Island of New Zealand. From its source on the Hakaru River, it flows generally south, with most of its length being through a drowned valley in the northeast of the Kaipara Harbour system. The estuarine section of the river forms a part of the border between the Kaipara District of the Northland Region and the Rodney local board area of the Auckland Region. The Topuni River flows into Oruawharo River — an arm of the Kaipara — 10 kilometres northwest of Wellsford.

• List of rivers of New Zealand

"Place name detail: Topuni River". New Zealand Gazetteer. New Zealand Geographic Board. Retrieved 12 July 2009.