MK Dons boss Danny Wilson said: "Atletico Madrid will be an absolute mega game down here. There will be some massive stars coming here and they're one of the biggest clubs in Spain.
"From the players' point of view, it'll be a terrific test, pitting their wits against some very skilled and capable players.
"It'll be very interesting to see how they do and I'm really looking forward to that one."
The match has been scheduled for Sunday July 31, with a 2pm kick-off.
Meanwhile, the Dons have completed the signing of Hull striker Aaron Wilbraham.