9 Apr 1921 – 8 May 1921
| Athletic Bilbao|
| 1911 Copa del Rey, 1912 Copa del Rey, 1924 Copa del Rey, 1906 Copa del Rey, 1907 Copa del Rey|
The Copa del Rey 1921 was the 21st edition of the Copa del Rey, the Spanish football cup competition.
The competition started on April 9, 1921, and concluded on May 8, 1921, with the Final, held at the San Mamés in Bilbao, in which Athletic Bilbao lifted the trophy for the 8th time ever with a 4–1 victory over Athletic Madrid.
Biscay: Athletic de Bilbao
Gipuzkoa: Real Unión
Center Region: Athletic Madrid
South Region: Sevilla FC
Galicia: Fortuna Vigo
Asturias: Sporting de Gijón
Catalonia: FC Barcelona
Levante: SR Levante
1921 Copa del Rey Wikipedia
FC Barcelona withdrew in protest of the decision of Spanish Federation of moving the site of final from Seville to Bilbao. Athletic Madrid, his opponent, qualified for the semifinals.
Fortuna Vigo and Real Unión won one match each. At that year, the goal difference was not taken into account. A replay match was played.
Athletic Bilbao qualified for the semifinals.
Sevilla FC qualified for the semifinals.
Real Unión qualified for the semifinals.
Athletic Madrid qualified for the final.
Sevilla FC won the semifinals, but was disqualified because of illegal line up in quarter finals. Athletic Bilbao qualified for the final.