She has not decided on whether to participate in the balance beam final, which is scheduled for Tuesday. She earned bronze in the event in Brazil five years ago.
Biles had previously opted out of the all-around final, as well as the vault and uneven bars finals.
"Simone has withdrawn from the event final for floor and will make a decision on beam later this week," a tweet from USAG read. "Either way, we're all behind you, Simone."