On 21 July 2006, del Horno returned to Spain to sign for Valencia CF on a six-year contract worth €8 million, seen as a natural replacement for Amedeo Carboni who had retired at 41. Athletic Bilbao had expressed interest, but withdrew from further negotiations, forfeiting any further financial advantage; following surgery on his injured Achilles heel, which kept him off the pitches for most of the season, he made his debut for his new team on 3 March 2007 in a 1–0 home win over RC Celta de Vigo.