The double Rugby World Cup-winning flanker was among many regulars rested by the title-holders for a 64-21 victory over second-tier Portugal in Bloemfontein last Saturday.
South Africa face Australia in the opening round of the southern hemisphere competition on August 10 in Brisbane and they meet again in Perth seven days later.
Kolisi is among 22 World Cup winners chosen by coach Rassie Erasmus, with the biggest surprise being the inclusion of Bulls lock Ruan Nortje.
Nortje was not selected for several pre-season training camps and could not be considered for the opening Test of this season, a win over Wales in London last month, due to club commitments.
"The injury to Franco Mostert opened the door for Ruan Nortje to make his comeback to the national team," said Erasmus.
Nortje joins Eben Etzebeth, RG Snyman and Salmaan Moerat, who skippered South Africa against Portugal in only his seventh Test appearance, as the lock options.
Injuries ruled out a number of high-profile Springboks, including scrum-half Faf de Klerk, loose-head prop Steven Kitshoff and lock Mostert, while No. 8 Jasper Wiese is suspended.
Wiese is serving a six-match ban after being red-carded playing for Leicester Tigers in the English Premiership. He will be available for a home Test against New Zealand on August 31.
Hooker Malcolm Marx and flanker Pieter-Steph du Toit have been chosen after recovering from injuries sustained in a drawn home series with Six Nations champions Ireland this month.
Five newcomers retained
Five Springboks capped for the first time this season -- utility back Sacha Feinberg-Mngomezulu, scrum-half Morne van den Berg, prop Jean-Hendrik Wessels, hooker Johan Grobbelaar and flanker Ben-Jason Dixon -- will travel to Australia.
"We have included a few younger players who made strong statements in the Tests so far this season," said Erasmus.
Feinberg-Mngomezulu, who can operate at fly-half, centre and full-back, and Dixon have been the stand-out debutants this year.
"This is a quality group of players, which includes a mixture of youth and experience, and we believe this is the best group we could select for this tough assignment," added Erasmus.
"Australia are a quality team, and we have seen historically that they are a force to be reckoned with at home.
"We rested some players for the match against Portugal to recharge for this competition and are excited to see the energy they will bring back to the squad.
"While this may be a very different challenge to facing Wales, Ireland and Portugal, we have full faith in the players to make another big step up against southern hemisphere teams."
Squad
Forwards
Ben-Jason Dixon, Pieter-Steph du Toit, Thomas du Toit, Eben Etzebeth, Johan Grobbelaar, Vincent Koch, Siya Kolisi (capt), Elrigh Louw, Frans Malherbe, Malcolm Marx, Bongi Mbonambi, Salmaan Moerat, Ox Nche, Ruan Nortje, Kwagga Smith, RG Snyman, Gerhard Steenekamp, Marco van Staden, Jan-Hendrik Wessels
Backs
Lukhanyo Am, Kurt-Lee Arendse, Damian de Allende, Aphelele Fassi, Sacha Feinberg-Mngomezulu, Cheslin Kolbe, Jesse Kriel, Willie le Roux, Makazole Mapimpi, Manie Libbok, Handre Pollard, Cobus Reinach, Morne van den Berg, Grant Williams
Coach: Rassie Erasmus (RSA)