A magnitude 5.2 earthquake occurred in the Fiordland area at 7.41am on Thursday.
It was centred 5km east of Milford Sound, at a depth of 6km.
GNS Science said it was felt as far north as Christchurch.
Police in Queenstown said there were no reports of damage.
A number of smaller shallow quakes have since been recorded in the area. AAP reports the biggest registered magnitude 4.0.