The Brazil legend believes his compatriot will be one of the nation's greatest players of all time if he continues on his current track.
The 21-year-old shined in 2013. After signing for the Catalans from Santos in the early summer, he starred as the Selecao stormed to the Confederations Cup title and has subsequently starred for Gerardo Martino's men this season.
"It is a fact that Neymar will be a great player," Ronaldo told Brazilian television. "He will go down in history as one of the best Brazilian players in the world. He's on the right track. He's a charismatic player and is focused on what you have to do to succeed."
The Blaugrana are in the midst of a winter break but they are back in action against second-place Atletico Madrid, which is level on points with the club.