Barcelona and Real Madrid were paired together in Friday's Copa del Rey semi-final draw, with Real Betis meeting Valencia in the other last-four tie.
The draw means Spain's two biggest clubs will play each other three times in the space of four weeks, with Madrid hosting Barca in La Liga on March 2.
Thirty-times winners Barcelona, who have won the last four editions of the competition, will host Real in the first leg on Feb. 6, with the second leg coming on Feb. 27 at the Santiago Bernabeu.
Betis will play at home to Valencia in the first leg and visit Mestalla in the second, with both ties being played on the same dates.
The final will be played at Betis' Benito Villamarin stadium in Seville on May 25.
Barca overcame a 2-0 deficit from their quarter-final first leg against Sevilla, thrashing the Andalusians 6-1 in the return leg to progress 6-3 on aggregate.
Real Madrid had a more comfortable path to the last four, beating Girona 4-2 at home and winning 3-1 away for a 7-3 aggregate win.
Betis meanwhile beat Espanyol 4-2 on aggregate, with Valencia overcoming Getafe 3-2 on aggregate by scoring twice in stoppage time in their 3-1 victory in the second leg at Mestalla.