Federation chief and UEFA vice president Angel Maria Villar was examined throughout the day along with his son Gorka by high court judge Santiago Pedraz who was set to rule on whether to free the pair on bail or jail them.
Also examined were federation vice-president Juan Padron and Ramon Hernandez Baussou, general secretary of the Tenerife federation.
They face charges including falsifying documents, appropriation of funds, collusion and administrative breaches linked to skimming profits from international friendly games and channelling the funds to Gorka Villar.
Investigators were also probing whether national federation funds had been used to bribe regional officials to vote for Villar at federation elections for president, according to Spanish media reports.
Villar, 67, a senior vice president of FIFA, has headed the Spanish federation since 1988.
He was arrested Tuesday following raids on federation headquarters and others sites as part of a fraud probe launched last year.
Under his watch Spain became one of the dominant forces in world football, winning two European championships and the 2010 World Cup.
But his critics say his period in charge was marked by ethical issues and an autocratic management style.
Following his re-election in May, El Pais newspaper denounced his “despotic” management and bemoaned his close ties to FIFA and UEFA leaders embroiled in corruption probes.