The experienced duo missed last week's 63-30 thrashing of Japan in Yokohama, with fly-half Foley sidelined through illness and scrum-half Genia ruled out with a calf problem.
They are both fit for the match at the Principality Stadium.
Reece Hodge moves back to the wing in place of Henry Speight, who starred against 2019 World Cup hosts Japan.
Samu Kerevi has retained his spot in midfield alongside fellow centre Tevita Kuridrani, with Kurtley Beale again chosen at fullback.
Utility back Karmichael Hunt is on the bench following a neck problem, having had his Rugby Championship campaign ruined by injury.
"I think Samu’s a very, very good player and I know he hasn’t had it all his way this year so I'm eager to see him fight back and hold a spot in the team," Australia coach Michael Cheika said after announcing his side in Cardiff on Thursday.
"A really good thing for us is we’ve got options around how we can set up because Karmichael can go to fullback or centre, Samu can go 12 or 13, Hodge can play pretty much anywhere now, and Beale can play 12, fullback or fly-half if we need.
"There was a lot happening last week, we lost a lot of players between that Barbarians game (against Australia) then the tour.
"If you look at our team, a lot of players haven’t got much experience playing in the northern hemisphere so it's good to have some experience around them this week," Cheika added.
Australia have won their last 12 Tests against Wales but will be up against a new-look side which was unveiled by home coach Warren Gatland earlier on Thursday.
Kurtley Beale; Marika Koroibete, Tevita Kuridrani, Samu Kerevi, Reece Hodge; Bernard Foley, Will Genia; Sean McMahon, Michael Hooper (capt), Ned Hanigan; Adam Coleman, Rob Simmons; Sekope Kepu, Tatafu Polota-Nau, Scott Sio
Replacements: Stephen Moore, Tom Robertson, Allan Alaalatoa, Matt Philip, Ben McCalman, Nick Phipps, Karmichael Hunt, Henry Speight