The reports, dating from 1954 to 2009, were released under freedom of information laws after the New Zealand Defence Force removed names and other identifying material.
In about 2,000 pages of documents, members of the public, military personnel and commercial pilots outline close encounters, mostly involving moving lights in the sky.
Some of the accounts include drawings of flying saucers, descriptions of aliens wearing “pharaoh masks” and alleged examples of extraterrestrial writing.
One of the most comprehensive files concerns two sightings of strange lights off the South Island town of Kaikoura in 1978, one of which was captured by a television crew aboard a plane in the area.
The incident made international headlines at the time but a contemporary Air Force report found it could be explained by natural phenomena such as lights from boats being reflected off clouds or an unusual view of the planet Venus.