Both players missed last weekend’s defeat at Brentford and Grealish has not featured since May 17.
But De Bruyne and Grealish have trained this weekend and are expected to come back into the City team when they face Manchester United at Wembley.
Ruben Dias and Manuel Akanji also missed the Brentford game but will return and Pep Guardiola has no fresh injury concerns.
Back-up goalkeeper Stefan Ortega will start at Wembley in place of Ederson.
Ortega has started all domestic cup competitions this season and his inclusion is a big call after Zack Steffen’s high-profile mistakes in last year’s semi-final defeat by Liverpool.
“He is going to play,” said Guardiola. “I have always been like that in the FA Cup. At Barcelona and Bayern as well. The keeper who plays in the FA Cup is going to play.”
When asked about the fitness of De Bruyne, Grealish and Dias, Guardiola said: “They trained well last two sessions. They are all of them more or less fine.”
Predicted Manchester City XI (3-2-4-1): Ortega; Walker, Dias, Akanji; Stones, Rodri; Silva, De Bruyne, Gundogan, Grealish; Haaland.