The 30-year-old is part of the 28-man squad named on Wednesday as Australia head to Cape Town and Mendoza to complete their Rugby Championship campaign.
Ashley-Cooper missed the Wallabies' win over Argentina on the Gold Coast on Saturday due to a nerve compression injury.
Others returning include scrum-half Will Genia, prop Benn Robinson and hooker Saia Fainga'a.
Wallabies coach Ewen McKenzie was happy to add experience to his squad.
"It's pleasing to be able to bring in some experienced guys for what will be an extremely challenging tour of South Africa and Argentina," he said.
"We took a conservative approach with Adam's injury in our most recent Test against Argentina, and we're confident the additional week off will serve him well going into the next stage of our campaign.
"Collectively, we add almost 250 games of Test experience to our squad through the inclusion of Adam, Will, Benn and Saia.
"They've all had good exposure to our program this year, so we expect them to be able to contribute immediately when we get into camp."
ACT Brumbies hooker Josh Mann-Rea is also part of the squad and could earn his first Test cap.
Wallabies squad: Ben Alexander, Pek Cowan, Sekope Kepu, Benn Robinson, James Slipper, Saia Fainga'a, James Hanson, Josh Mann-Rea, Sam Carter, James Horwill, Rob Simmons, Scott Fardy, Scott Higginbotham, Matt Hodgson, Michael Hooper, Ben McCalman, Will Genia, Nick Phipps, Nic White, Kurtley Beale, Bernard Foley, Tevita Kuridrani, Christian Lealiifano, Matt Toomua, Adam Ashley-Cooper, Israel Folau, Rob Horne, Joe Tomane.