The Belgian duo spent last season out on loan but the new boss believes both players are ready to be compete for a first-team place at Stamford Bridge next season.
Lukaku spent last term on loan at West Brom, where he scored 17 goals in 35 Premier League appearances, while De Bruyne shone in midfield for Werder Bremen during his season-long stint with the Bundesliga club.
Both players have been linked with loan moves ahead of the new campaign -- with De Bruyne part of a speculated swap to Bayer Leverkusen for Andre Schurrle -- but Mourinho revealed in his first Chelsea press conference that the two Belgium internationals are ready for first-team football at Stamford Bridge.
"First of all I want to meet them. And I think it's fair that the players are the first ones to know about their future and to know about their future by their manager and their club and not by the media," Mourinho said. "I can say that [De Bruyne and Lukaku] are the profile of player that Chelsea invested a lot in the past, and I think it's my work and my contribution to extract the best out of that investment, and I think both of them are ready to come and are ready to be part of our squad."