A new museum will display the private antiques collection of Adelaide man David Roche, a collector since his teenage years who died in 2013.

More than 3,500 items collected over almost six decades will go on show to the public, including furniture, ceramics, metalware, clocks and paintings dating back as far as the 18th century.

The museum has been established in his former home in Melbourne Street, North Adelaide, and a purpose-built adjoining gallery.

It was Mr Roche's wish that his collection be enjoyed by the general public, director of the David Roche Foundation House Museum, Martyn Cook, said.

"He rarely showed anybody through his house, he was very shy," he said.

"He was very keen that when he was gone people would be able to look at his collection."

Mr Roche was born in 1930 and started collecting when he was 17.

He was still purchasing antiques just months before his death.

Museum curator Robert Reason said the Adelaide public had been given an incredible opportunity to share in the world-class collection.

"For a man to decide that he'll leave that collection and his entire estate to the public I think is unusual — it's an incredible opportunity that's allowed us to open his house," he said.

"Some of those items are unique in the world and could fit into any collection anywhere so we're very fortunate to have them available here in Adelaide."

Former prime minister Paul Keating will officially open the museum and gallery on Friday evening and it will be open to the public from next Tuesday.