Lampard won two Premier League titles under Jose Mourinho during his two different spells at Chelsea, so not many know the Portuguese manager better than him.
The former England midfielder claims the Manchester United boss had a massive influence on his career but says he is not every player’s cup of tea.
“He’s demanding, he’s a demanding manager,” Lampard said on BT Sport.
“He likes conflict, he kind of promotes the conflict, not in the group but outside and we’ve seen that, it’s very much a family thing.
“He changed my career personally when he came in, he gave me a self confidence.
“He’s very confident in himself, he portrays that to his players, I really enjoyed it.
“But some players can find him too demanding.”
The 54-year-old, who won three pieces of silverware in his first season at Manchester United, is the self-proclaimed “Special One”.
Jose Mourinho plays down that tag now but Lampard says he is one of the best managers in the world.
“There are special ones and I know he plays himself down,” Chelsea‘s all-time leading goalscorer added.
“He’s certainly one of the best managers in the world, his record speaks for itself.
“Personality, his tactical nouse, I think we saw that last year, particularly in the Europa League final.”
Mourinho’s next game in charge of United is against Everton this Sunday at Old Trafford (4pm).