Zouma, 20, has made an impressive start to his career at Chelsea – making 15 appearances in all competitions in his first season.
Mourinho said Zouma was different to 34-year-old Terry, but tipped him to eventually mature into Chelsea captain.
"They [Terry and Zouma] are different players. Sometimes you get replicas of players," the Portuguese manager was quoted as saying by The Mirror.
"Other times you can't do it, and if you can't Zouma now is 20, so one day Zouma will be 23 or 24 and will be a player of great maturity and probably leadership, too, to replace John.
"Zouma is playing more than I expected, more than he expected, more than everyone expected. So he's getting very important experience."
Mourinho said Zouma had already reached a level where he is competing with Gary Cahill for a spot in the centre of defence.
He hopes an international call-up with France can help him improve quickly.
"When he gets caps with France and is playing with Chelsea at this level his development will have an acceleration," Mourinho said.
"We bought him because of his physical profile, but we were not happy with his tactical knowledge of the game.
"We trusted we could give that to him. In pre-season, I saw mistakes in Germany against Werder Bremen. Mistakes in Hungary against Ferencvaros.
"I thought 'No problem, it will take time'. He's bright, humble, wants to work and learn, listens and is intelligent, so he's had an acceleration in that process to bring him to a level where he is competing with Gary Cahill."
