The forward, one of the biggest names at the tournament, suffered the injury when he collided with the shoulder of Austrian defender Kevin Danso while challenging for a header.
He was substituted near the end and left the stadium in an ambulance to undergo X-rays.
"Kylian Mbappe suffered a broken nose during the second half of the Austria v France match this Monday in Duesseldorf," a statement from the federation said.
"The captain of the French team was first taken care of by the medical staff and doctor Franck Le Gall, who diagnosed a broken nose. Diagnosis confirmed during radiological examinations at the Duesseldorf hospital.
"Kylian Mbappe has returned to the base camp of the French team. He will undergo treatment in the coming days, without undergoing surgery immediately."
France face the Netherlands on Friday and Mbappe is now a doubt for that clash - a huge blow for France.
"A mask will be made so as to allow the number 10 of the French team to consider resuming competition after a period devoted to treatment," the FFF said.
