A rusting cockroach sculpture has been given a new home, for now, in Adelaide's main city retail strip.

The cockroach, about four metres long and almost as wide, was erected in a paddock just north of Adelaide as a protest during the 1990s when a waste dump was proposed for the area.

When it was noticed the cockroach was gone from the paddock recently, a Facebook campaign was started to seek its return.

Local TV host Andrew Costello was behind the social media campaign and tracked the cockroach down to a scrap metal yard north of Adelaide.

Tourism Minister Leon Bignell says an unusual transaction was arranged to save the sculpture.

"Cosi purchased the cockroach for two slabs of beer," he said.

"He's now very generously decided that rather than house the cockroach in his pool room, he'll donate it to the people of South Australia."

Mr Bignell says the sculpture will have a home in the heart of the city for the next month, but plans are being made to return it to its original habitat.

"The cockroach has been lovingly cleaned up and will call Rundle Mall home for the next four weeks or so, giving shoppers and city visitors an opportunity to admire its form and maybe even take a selfie," he said.

"Planning is underway to ensure it returns permanently to its rightful home on Port Wakefield Road at Lower Light."