Du Preez, who has been playing in Japan for the last two years, has been given permission by his club Suntory Sungoliath to feature in South Africa's three home matches in the southern hemisphere championship as coach Heyneke Meyer looks to reintegrate him into the side ahead of the 2015 World Cup.
His selection is a sign of a major shift in strategy from the South African Rugby Union, who have begrudgingly accepted they can no longer ignore overseas-based players as the top talent continues to oly their trade Europe and Japan.
Other players signed with overseas clubs included in the squad are flyhalf Morne Steyn, winger Bryan Habana, lock Juandre Kruger, flank Francois Louw, scrumhalves Ruan Pienaar and Jano Vermaak, and prop Gurthro Steenkamp.
Piet van Zyl will replace Du Preez in the Rugby Championship squad for the games when the 31-year-old will be unavailable for selection.
"Fourie has been out of international rugby for a while and it makes sense to involve him as soon as possible," Meyer said in announcing the squad captained by centre Jean de Villiers.
"Piet was part of the squad in June and we know what he can do - he will slot in without any problems when necessary."
Also included are Stormers loose forward Duane Vermeulen, who returns from injury, and Toulouse prop Steenkamp.
"It's great to have Duane back after he played such an important role for us at the end of last season," Meyer added.
"It will also be good to see Gurthro back in the mix.
"Along with Fourie, they boast 102 tests worth of experience between the two of them, have been part of very successful teams before and will be able to share a lot of knowledge with the younger players around them."
The Springboks open their Rugby Championship campaign against Argentina in Soweto Aug. 17, before heading to Mendoza to meet Los Pumas again on Aug. 24.
South Africa squad:
Forwards: Willem Alberts, Marcell Coetzee, Bismarck du Plessis, Jannie du Plessis, Eben Etzebeth, Siya Kolisi, Juandre Kruger, Francois Louw, Tendai Mtawarira, Trevor Nyakane, Coenie Oosthuizen, Chiliboy Ralepelle, Gurthro Steenkamp, Adriaan Strauss, Flip van der Merwe, Franco van der Merwe, Duane Vermeulen.
Backs: Bjorn Basson, Juan de Jongh, Jean de Villiers (captain), Fourie du Preez, JJ Engelbrecht, Bryan Habana, Zane Kirchner, Pat Lambie, Willie le Roux, Ruan Pienaar, Jan Serfontein, Morne Steyn, Jano Vermaak.