The Blues boss has been fulsome in his praise of the likes of Nathaniel Chalobah - now on loan at Nottingham Forest but told he will be part of the
Chelsea first-team next season - and is optimistic the club's academy can bear further fruit.
Mourinho told the Guardian: "Ideally it's not just about having British players either, but having players who are made in Chelsea.
"In three or four years' time, if we don't have other Englishmen to replace this nucleus of players - when Lamps is 39, John is 36 - I will be very sad.
Every club needs that. So we are working on that (new generation)."
Terry, Cole and Lampard are all out of contract at the end of the current campaign.
Terry, more than his team-mates, has enjoyed highs - lifting silverware, including the 2012 Champions League - and endured lows - the racism row, twice losing the England captaincy, injury and missing a penalty in the 2008 Champions League final - since Mourinho's 2007 departure.
The Portuguese believes the captain is rediscovering his best form since his summer return for a second spell as boss at Stamford Bridge.
"Even I was questioning, from far away, what was happening to this guy: physical problems, psychological problems, what is going on?" Mourinho said.
"I'm happy he's proving he's still a top player."