Chris Henry and Declan Fitzpatrick are on the bench for Saturday's game against the Grand Slam champions in Cardiff.
Ireland have restored Brian O'Driscoll, Rob Kearney and Sean O'Brien, as well as Best, to their XV after the influential quartet missed the summer schedule due to injury.
However O'Driscoll will be relieved of leadership duties after coach Declan Kidney's decision to appoint number eight Jamie Heaslip skipper.
The 34-year-old renews his centre partnership with Leinster team-mate Gordon D'Arcy.
Jonathan Sexton and Conor Murray have been selected at half-back, meanwhile Kearney joins the exciting duo of Gilroy and Simon Zebo in the back three.
"It was a tight call because there's so much competition," said Kidney.
"Fergus McFadden and Keith Earls have been playing well, so it's testament to the way Craig and Simon have been playing that they're selected."
Meanwhile, after playing for the Irish Wolfhounds, Andrew Trimble was surprisingly left out of the squad.
Kickoff is at 1.30pm on Saturday.
Ireland team: Rob Kearney, Craig Gilroy, Brian O'Driscoll, Gordon D'Arcy, Simon Zebo, Jonathan Sexton, Conor Murray, Cian Healy, Rory Best, Mike Ross, Mike McCarthy, Donnacha Ryan, Peter O'Mahony, Sean O'Brien, Jamie Heaslip.
Replacements: Sean Cronin, David Kilcoyne, Declan Fitzpatrick, Donncha O'Callaghan, Chris Henry, Eoin Reddan, Ronan O'Gara, Keith Earls.