Ospreys director of coaching Scott Johnson will prepare the Barbarians backs to face Wales at Cardiff's Millennium Stadium on Saturday, 4 June.
Johnson, who coached Wales for three games in 2006, will work alongside Cardiff Blues coach Dai Young.
The Barbarians squad includes Sergio Parisse, Doug Howlett and Seru Rabini.
"It's been a while since I've coached at the Millennium Stadium but the place is full of fantastic memories for me," said Australian Johnson.
"I had a great time as Wales coach and the 2005 Grand Slam [as assistant to Mike Ruddock] has got to be the highlight of my international coaching career.
"We played just two games at home, but that final decider against Ireland was just one of those epic games and something that will stay with everyone who experienced it forever.
"The Barbarians are steeped in tradition, they come with their own style and attitude and with so many experienced international players the side would probably coach itself, but it's an exciting prospect and a privilege to be involved."
Wales will award caps for the game - only the third time they have decided to do so against the Barbarians.
The game has been organised to commemorate the 130th anniversary of the Welsh Rugby Union's formation, and coach Warren Gatland has already announced that flanker Sam Warburton will captain his country for the first time.
Warburton's opposite number is set to be his Cardiff Blues team-mate Martyn Williams, who was left out of Wales's Six Nations squad this year.
Williams, 35, says he still hopes to win a place in Warren Gatland's World Cup squad.
He is likely to form a classy back-row combination for the Barbarians with Italy captain Sergio Parisse and Australia great George Smith.
Other stars lined-up to face Wales include Springboks Ruan Pienaar, Francois Steyn and Joe van Niekerk, All Blacks prop Carl Hayman, Ireland prop John Hayes, France centre Mathieu Bastareaud, plus England three-quarters Paul Sackey and Iain Balshaw.
"Facing Wales at the Millennium Stadium would be a daunting prospect for any coach or player and there are obviously going to be a few Ospreys in that Wales side as well, a few guys who I know pretty well, so it's going to be interesting to see how the game pans out," added Johnson.
"Myself and Dai [Young] go back a long way too and there's one thing that everyone in that Barbarians squad will definitely have in common, apart from the desire to entertain, and that's going to be a pretty resolute determination to win."
Forwards: P James (Ospreys), J Yapp (Cardiff Blues), R Bevington (Ospreys), S Andrews (Cardiff Blues), H Bennett (Ospreys), R Hibbard (Ospreys), L Burns (Newport Gwent Dragons), A-W Jones (Ospreys), R Jones (Ospreys), L Charteris (Newport Gwent Dragons), L Reed (Scarlets), D Lydiate (Newport Gwent Dragons), T Faletau (Newport Gwent Dragons), J Turnbull (Scarlets), S Warburton (Cardiff Blues, capt).
Backs: M Stoddart (Scarlets), G North (Scarlets), A Brew (Newport Gwent Dragons), S Williams (Ospreys), J Davies (Scarlets), S Williams (Scarlets), G Henson (Toulon), S Jones (Scarlets), R Priestland (Scarlets), M Phillips (Ospreys), T Knoyle (Scarlets).
Barbarians squad (to be finalised):
Forwards: Leonardo Ghiraldini (Treviso/Italy), Iestyn Thomas (Scarlets/Wales), Carl Hayman (Toulon/New Zealand), Paul Tito (Cardiff Blues/uncapped), Erik Lund (Biarritz/Norway), Joe van Niekerk (Toulon/South Africa), Iosefa Tekori (Castres/Samoa), George Smith (Toulon/Australia), Martyn Williams (Blues/Wales), Sergio Parisse (Stade Francais/Italy).
Backs: Iain Balshaw (Biarritz/England), Seru Rabini (Fiji), Paul Sackey (Toulon, England), Matthieu Bastareaud (Stade Francais/France), Doug Howlett (Munster/New Zealand - only available v Wales on 4 June), Ian Humphreys (Ulster/uncapped), Frederic Michalak (France), Ruan Pienaar (Ulster/South Africa - available only v England 29 May).