The floodlit friendly will see John Toshack's exciting young squad - featuring home-based talent such as Ashley Williams of Swansea City and Joe Ledley of Cardiff City - do battle with Luxembourg.
This will be the second time that the FAW have played at Parc y Scarlets, the first fixture was played against Estonia in June 2009.
Parc y Scarlets has previously staged the Under 21 UEFA qualifier between Wales and Luxembourg in March 2009 and has staged two Welsh Cup Finals.
Scarlets Operations Director Jon Daniels said: "This is excellent news for the stadium. Following on from last year's senior fixture and the Welsh Cup Final held here in May of this year it goes to show that Parc y Scarlets is a great venue for other activities as well as rugby.
"The keenness of the FAW to return to Parc y Scarlets underlines the quality of the stadium and its staff, the ground's great flexibility and our determination to make it one of our country's most dynamic venues."
Parc y Scarlets first played host to soccer on March 31, 2009 when the Wales U21 side beat Luxembourg 5-1 in the second game of their UEFA Championship.
Wales v Luxembourg, Wednesday 11th August, kick off 7.45pm.
Ticket prices for the international will be: Adults £10, Juniors (Under 16) £5, for all parts of the ground. These prices are plus a booking fee. Tickets are available from Parc y Scarles Ticket office on 0871 871 8088.
