The France international suffered a stress fracture in his left foot in the semi-final win over Bayern Munich on May 8th.
Ancelotti said he thought the 24-year-old would be fit to play for France at Euro 2024, which starts on June 14th.
"He's working individually, he won't be ready for the final - he's ruled out for that," Ancelotti told a news conference Friday.
"I think he will recover for the Euros, I think he can recover."
Los Blancos face German side Borussia Dortmund at Wembley on June 1st aiming to win the Champions League for a record-extending 15th time.
Tchouameni's compatriot Eduardo Camavinga may start at the base of the midfield.
La Liga champions Real Madrid face Real Betis on Saturday in their final league game before the final against Dortmund in London next week
