Newcastle can expect a sell-out crowd for the game, which is sure to attract a massive interest ahead of the club's long-awaited return to the Champions League - United are in the qualifying round just eight days later.
Barcelona will also have to qualify for the group stage having finished fourth in the Primera Liga last season.
The last time the two sides met was in September 1997, when a hat-trick from Tino Asprilla ensured a 3-2 triumph.