United beat Stranraer on Saturday to progress to quarter-finals.
Dundee United will travel to East End Park to face Dunfermline in the quarter-finals of the Irn-Bru Challenge Cup.
The tie which will take place on the weekend of November 12, will be the third meeting between the sides in three different competitions this season.
The Tangerines beat the Pars 2-0 in the League Cup in July and then 3-1 in the Championship last month when United keeper Cammy Bell memorably saved three penalties.
The two sides were already due to meet at Tannadice on November 12 on league business with that game now being postponed.
In the other quarter-final ties, Welsh side The New Saints, who beat Forfar at Station Park on Saturday, will return to Scotland to play Livingston, Queen of the South are at home to Alloa while St Mirren entertain Ayr United.
