Nadal won the clay court title match 7-6 (7-1), 7-5, taking advantage of a string of unforced Ferrer errors in the first-set tiebreaker and erasing a 5-4 deficit in the second frame as Ferrer failed to capitalize during his service game.
Nadal, the defending champion, met Ferrer for the fifth time in Barcelona, including the fourth time in the final and second year in a row.
The top seed, who also took last week's ATP Masters event in Monte Carlo, has won the last 32 sets he's played on Barcelona's clay courts and improved to 14-4 lifetime against Ferrer.
Ferrer was seeking his 15th career title and fourth of the year following earlier victories in Auckland, Buenos Aires and Acapulco.
Celebrity Families of 2014 [PHOTOS]