Mongonui may refer to:
Mangōnui, New Zealand settlement in Northland which used to be called Mongonui Mongonui (New Zealand electorate), the electoral district under that name Newstead railway station, a former railway station previously named Mongonui in Waikato, New Zealand
See also Mangonui County, formerly known as Mongonui County Mongonui and Bay of Islands (New Zealand electorate), another electoral district using the name