De Bruyne was substituted late in Saturday's Premier League win at Everton after sustaining a groin injury.
And City have now confirmed the midfielder will not be able to take part in the Group C game against Dinamo, who thrashed Atalanta in their opener.
A City statement said: "The extent of his layoff depends on how well he responds to the rehabilitation programme overseen by the club's medical staff."
De Bruyne has recorded nine assists in nine appearances for the Premier League champions this term.
He will be a big miss for Pep Guardiola’s side after being forced back onto the sidelines.
The 28-year-old sat out large periods of last season after being struck down with a series of niggling knocks.
Guardiola had hoped to see the end of such fitness struggles, with De Bruyne considered to be a key man for the reigning Premier League champions.
“Kevin sometimes is a special player,” Guardiola told City's official website.
“He sees things others cannot see on the pitch, or even off the pitch. Sometimes he frustrates me when he loses simple balls. How can he lose it with his quality?
“But he is an incredibly talented player, with his vision up front and the quality of his shooting.
“With Kevin it depends on his mood. Sometimes it is low but when he is happy, he's an incredible, fantastic player.
“We missed him a lot. We had an incredible season, winning four titles, but we missed him a lot.
“He’s a special player. I’m happy he is here.”
City won 3-0 away to Shakhtar Donetsk in their first Champions League group game two weeks ago and will be looking to make it six points from six despite seeing De Bruyne ruled out.