"Jose Mourinho will have his opinion, but right now Leo is the best in the world and maybe ever. Cristiano is a good player, but Messi sets the bar," Alba told Movistar.
Meanwhile, Alba has also praised David Villa, who has returned to the team this season following an injury layoff.
"David Villa is in a great state of mind. He'll continue to be important for the team," he added.
Alba joined Barca from Valencia in the summer.