Full-back Liam Williams has been passed fit to play after going off with a shoulder injury during the 18-11 victory over Scotland last time out.
Gatland guided Wales to clean-sweep glory in 2008 and 2012 and, like Ireland coach and fellow New Zealander Joe Schmidt, he takes charge of a final Six Nations match in Cardiff before a 2019 World Cup swansong.
"We've named an unchanged squad and rewarded the players for the last couple of outings and the last couple of victories," said Gatland.
"These players are on a very good run, they are a hugely impressive group and they deserve to be going into the final weekend with everything to play for.
"It is a great reward for them for the hard work they have put in and we are all looking forward to what is going to be a huge game.
"For a number of us as coaches this is our last Six Nations game and the fact that it is in Cardiff is extra special. There is bound to be a bit of emotion on Saturday and that is something to embrace."
Captain Alun Wyn Jones will equal Gethin Jenkin's total Test appearance record on 134 caps – including nine with the British and Irish Lions – to sit joint fifth on the world all-time list.
Ireland, Wales and England – which faces Scotland – can all win the Six Nations heading into the final round of games.
Wales: Liam Williams, George North, Jonathan Davies, Hadleigh Parkes, Josh Adams, Gareth Anscombe, Gareth Davies; Rob Evans, Ken Owens, Tomas Francis, Adam Beard, Alun Wyn Jones (captain), Josh Navidi, Justin Tipuric, Ross Moriarty.
Replacements: Elliot Dee, Nicky Smith, Dillon Lewis, Jake Ball, Aaron Wainwright, Aled Davies, Dan Biggar, Owen Watkin.