The 2004–05 Copa Federación de España was the 12th staging of the

Copa Federación de España The Copa Real Federación Española de Fútbol, popularly known as the Copa Federación (Federation Cup) or Copa RFEF, is a Spanish football competition organised by the Royal Spanish Football Federation (RFEF). It has been held since the 1993−9 ...

. It is a knockout competition for

Spanish football Football is the most popular sport in Spain, with 61% of the population interested in it. Spain has some of the most influential teams in Europe (Real Madrid, Barcelona, Atlético de Madrid, Sevilla, Valencia, and others) as well as many playe ...

clubs in

Segunda División B Segunda División B (English: second division B) was the third tier of the Spanish football league system containing 102 teams divided into five groups, until it was replaced by the new structure in 2021. It was administered by the Royal Spanish ...

and

Tercera División Tercera División () was the fourth tier of the Spanish football league system. Until 1977, it was the third tier of the Spanish football league system. Founded in 1929, it was below the ''Primera División'' (also known as La Liga), the ''Segund ...

. The competition began in August 2005 with the Regional stages, and ended with the finals on 13 and 27 April 2005.