The bodies were that of a 32-year-old woman and 52-year-old man, police said. They were found about 12.30am at a house on Dundas Rd.
The pair were known to each other, police said.
Part of Dundas Rd was cordoned off this morning, with three vehicles - a red ute, a white BMW and a blue car - in the middle of the road appearing to form part of the police investigation.
It is not yet clear what connection they have to the inquiry, but residents on the street told the Northern Advocate they could not drive past the vehicles as police had set up a cordon around them.
One resident said she was forced to leave her car at home and walk to work because of the cordons.
She did not know the people in the house where the homicide inquiry was based and had not heard any disturbance there this morning.
Another resident said it was frightening to hear two bodies had been found in the neighbourhood and that a homicide investigation was underway.
It was believed a man lived in the house by himself.
A post mortem will be carried out on the man and woman in Auckland tomorrow.
Anyone who may have heard or seen anything in the Dundas Rd area between 11pm last night and 12.30am this morning is asked to contact Whangarei Police on 09 430 4500 or anonymously contact Crimestoppers on 0800 555 111.
