The 2005–06 Copa Federación de España was the 13th 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 for teams from the Segunda División B, the Tercera División and sometimes from the Preferent ...

, a knockout competition for

Spanish football Football is the most popular sport in Spain. Spain has some of the most important teams in Europe (Real Madrid, Barcelona, Atlético de Madrid, Seville, Valencia, and others). It also has a high number of players (most of them being unprofession ...

clubs in

Segunda División B Segunda División B ( en, 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 Foot ...

and

Tercera División Tercera División ( en, Third Division) was the fourth tier of the Spanish football league system. Founded in 1929, it was below the ''Primera División'' (also known as La Liga), the ''Segunda División'', and the semi-professional ''Segunda Di ...

. The competition began in August 2006 with the Regional stages and ended with the finals on 5 and 19 April 2006.