Wales have lost their last seven internationals since defeating Georgia in the World Cup and have not beaten the Wallabies in Australia since 1969.
Australia have a new head coach in Joe Schmidt who has taken over from Eddie Jones.
The Wallabies have also named an inexperienced team with a new skipper in flanker Liam Wright, and centre Josh Flook and lock Jeremy Williams making their debuts.
There are five newcomers among the replacements, including Tom Lynagh, who is the son of Wallabies World Cup winner Michael and brother of Italy international Louis.
Only prop James Slipper, number eight Rob Valetini and wing Andrew Kellaway started the World Cup record defeat against Wales in France last year.
“We’ve had a good week of preparations here in Sydney and are excited to get out on field on Saturday,” said Gatland.
“This first Test is going to be a great challenge for us.
“Test matches are all about fine margins and we know we need to be accurate, keep our discipline and stay in the fight for the full 80 minutes.
“There’s a lot of talent within the Australia squad and we know they will want to come out firing and put in a performance against us this weekend.”
Australia: Tom Wright; Andrew Kellaway, Josh Flook, Hunter Paisami, Filipo Daugunu; Noah Lolesio, Jake Gordon: James Slipper, Matt Faessler, Taniela Tupou, Jeremy Williams, Lukhan Salakaia-Loto, Liam Wright (capt), Fraser McReight, Rob Valetini.
Replacements: Billy Pollard, Isaac Kailea, Allan Alaalatoa, Angus Blyth, Charlie Cale, Tate McDermott, Tom Lynagh, Dylan Pietsch.
Wales: Liam Williams; Josh Hathaway, Owen Watkin, Mason Grady, Rio Dyer; Ben Thomas, Ellis Bevan; Gareth Thomas, Dewi Lake (capt), Archie Griffin, Christ Tshiunza, Dafydd Jenkins, Taine Plumtree, Tommy Reffell, Aaron Wainwright.
Replacements: Evan Lloyd, Kemsley Mathias, Harri O’Connor, Cory Hill, James Botham, Kieran Hardy, Sam Costelow, Nick Tompkins.
