O'Connor struggled in the pivotal position during the Wallabies' 23-21 loss in the first Test in Brisbane, but will have a chance to make amends in the match at Docklands Stadium.
Beale, who started on the bench last week and missed two late shots on goal that could have given the Wallabies victory, slots into full-back in place of the injured Berrick Barnes.
With Digby Ioane out of the series with a shoulder injury, ACT Brumbies back Joe Tomane lines up at the left wing for just his second Test a year after making his debut against Scotland.
Christian Leali'ifano, who was knocked out cold in the first minute at Lang Park in the briefest of Test debuts, was cleared of concussion and will retain the inside centre position.
The jet-heeled Leali'ifano was the Wallabies' designated kicker for the first Test and is likely to have the duty again after replacement kickers O'Connor and Beale missed a number of scoring chances at Lang Park.
The rugged veteran Adam Ashley-Cooper was also cleared to play after a shoulder injury in the first Test and lines up at outside centre.
Israel Folau, who scored two scintillating tries in a brilliant Test debut last week, retains his place on the other wing in a backline still potent despite the raft of injuries last week.
Deans has kept faith with the forward pack that outmuscled the Lions in two late scrums and won Beale the final penalty kick that he ultimately missed when he slipped over.
Prop Ben Alexander celebrates his 50th Test cap, while Michael Hooper retains his place at openside flanker, despite media speculation that 110-cap veteran George Smith might pressure him for the starting jersey.
The 32-year-old Smith, drafted into Wallabies camp this week after recovering from a knee injury, was left out of the match-day 23 altogether, with Liam Gill keeping the reserve flanker position.
Rob Horne has taken a spot on the bench in the absence of injured centre Pat McCabe, along with the uncapped but highly-rated full-back Jesse Mogg, who had a strong performance in the Brumbies' win over the Lions in Canberra last week.
Australia: 15-Kurtley Beale, 14-Israel Folau, 13-Adam Ashley-Cooper, 12-Christian Leali'ifano, 11-Joe Tomane, 10-James O'Connor, 9-Will Genia, 8-Wycliff Palu, 7-Michael Hooper, 6-Ben Mowen, 5-James Horwill (captain), 4-Kane Douglas, 3-Ben Alexander, 2-Stephen Moore, 1-Benn Robinson
Replacements: 16-Saia Fainga'a, 17-James Slipper, 18-Sekope Kepu, 19-Rob Simmons, 20-Liam Gill, 21-Nick Phipps, 22-Rob Horne, 23-Jesse Mogg