A final batch of 15 western quolls has been released in South Australia's Flinders Ranges in an ambitious program to return the native marsupials to the region after an almost 150-year absence.

Western quolls once roamed 80 per cent of Australia but their habitat has been reduced to the south-western corner of Western Australia.

The creatures disappeared from the Flinders Ranges in the 1880s but, since the re-introduction began at the Ikara-Flinders Ranges National Park in 2014, the population has increased to about 150.

About half of the current quolls were born in the park, with others relocated from the wild in Western Australia.

"We lost a few early on, but we introduced species that were predator-aware, so they knew how to handle themselves," Environment Minister Ian Hunter said.

"They seem to be holding on to their territory, and we think things are looking good but we'll continue to monitor for the next two years."

"This extra population in the Flinders Ranges is a great insurance policy for that species."

The western quoll program followed the successful re-introduction of the yellow-footed rock wallaby in the Flinders Ranges.

"We're also re-introducing brush tail possums which have disappeared from the region," Mr Hunter said.

"They were introduced in 2015 and they seem to be holding on well."

The State Government hopes the rebounding native wildlife will boost tourism.

"The return of the western quoll to the region has important meaning for the local Adnyamathanha people, and it is also expected that the tourism appeal of the Flinders Ranges will increase if the quoll population takes hold," Mr Hunter said.

Western quolls have been re-introduced through a partnership between South Australia, Western Australia and the Foundation for Australia's Most Endangered Species, a private organisation.