King's Cup draw pits Barca against Bilbao
The pair, who played the 2009 final which Barca won 4-1 as part of an unprecedented treble of La Liga, European Champions League and domestic Cup, will play their first leg at the Nou Camp on December 22 and the return leg in Bilbao on January 5.
Real Madrid, who have not won the Cup since 1993 and would not meet arch rivals Barca unless both reach May's final, will play Levante, while holders Sevilla face Malaga, the RFEF said on their website.
If they get past Athletic, Barca will play second-division Real Betis or La Liga rivals Getafe in the quarter-finals and could meet Real Mallorca or Deportivo Coruna in the last four.
Real are on course to meet Atletico Madrid in the quarters, if their city neighbours beat Espanyol, and possibly Villarreal, Valencia or Sevilla in the semis.