Ernesto Valverde's men, who host Valencia on Saturday, are already without star forwards Lionel Messi and Luis Suarez due to foot and calf problems respectively.
Winger Ousmane Dembele is also sidelined with a hamstring issue, while full-back Nelson Semedo has a sprained ankle.
"Tests carried out on Monday... Have shown that the Barca first-team player Samuel Umtiti has a bruised foot and his recovery will dictate when he returns," said a Barcelona statement.
"It is worth remembering that Umtiti picked up the injury with the French national side."
The 25-year-old World Cup-winner has yet to play for Barca in La Liga this season, watching from the bench as they dropped five points in their first three games.
Umtiti was not originally selected for Didier Deschamps' France squad for the September Euro 2020 qualifiers against Albania and Andorra, but was called up after Manchester City's Aymeric Laporte was ruled out with injury.
He now faces a race against time to be fit for Barca's Champions League opener at Borussia Dortmund a week on Tuesday.