A fire spokesman said it was a large vegetation fire, covering about 6ha.
Four helicopters are battling the flames and crews from Kaikohe, Kerikeri, Kaihu, Whangarei and the council Rural Fire Authority were attending.
"There are structures, including houses, at risk," the fire spokesman said.
"They are currently attempting to contain the fire and they are also putting foam over the houses at risk in an effort to protect them from the fire."
The spokesman said there were "multiple" houses in danger, whose occupants had been evacuated.A 12-tonne digger is on its way to the scene to help with firebreaks.
The Fire Service is suggesting people who live nearby close their doors and windows to stop smoke coming inside and have asked motorists to avoid the area if possible so fire crews have easy access.
