Never-before-seen video footage of the Apollo 11 moonwalk found in Australia will be shown at an awards ceremony in Sydney next week.

The footage of mission commander Neil Armstrong descending the ladder of the lunar module will be shown at the Australian Geographic Society Awards next Wednesday, Australian Geographic (AG) said in a statement.

Armstrong's descent will be among highlights of the historic 1969 moonwalk to be shown at the awards, at which lunar module pilot Buzz Aldrin will be the guest of honour.

Other footage to be shown includes digitally remastered images of Armstrong's first step on the Moon's surface, Aldrin's descent of the ladder, the reading of the plaque and the raising of the US flag.

It is the first time the highlights reel of the restored footage will be screened.

AG said the unseen footage of Armstrong was found after a 10-year search.

- AAP