The Reds will face Swansea City in the play-off semi-finals, following the final round of regular Sky Bet Championship fixtures.
Having drawn against Norwich City, Barnsley finished fifth in the Championship table, accumulating 78 points, meaning that they will play the first leg at Oakwell.
The first leg will take place on Monday, May 17 in South Yorkshire, kicking off at 8:15pm.
The second leg will take place on Saturday, May 22 at the Liberty Stadium, with a 5:30pm kick-off.
