Ōtāhuhu is a suburb of Auckland to the southeast of the city centre, on a narrow isthmus between an arm of the Manukau Harbour to the west and the Tamaki River estuary to the east. The isthmus is the narrowest connection between the North Auckland Peninsula and the rest of the North Island, being only some 1200 metres wide at its narrowest point, between the Ōtāhuhu Creek and the Māngere Inlet. As the southernmost suburb of the former Auckland City it is considered part of South Auckland.
The suburb's name is taken from the Māori name of a volcanic cone also known as Mount Richmond. The name refers to eating uncooked huhu grubs. In colloquial speech locals typically shorten the name to "Otahu".