Water mains were broken, windows were smashed and power lines fell in Wellington, the capital city.
This is the second time in three days powerful quakes have shaken the country.
The epicentre of the quake was between the north and south islands in the Cook Strait, 57 kilometres southwest off the coast of Wellington, and 10 kilometres under the water.
There were no immediate reports of injuries after the tremors. And, there were no tsunami warnings issued.
Aftershocks continue to rattle the area