The crash took place sometime Tuesday morning near 76th Street and South Lafayette Avenue in the city's West Chatham neighborhood.
CFD said the 11 people suffered non-life threatening injuries.
They said 10 patients were from the bus.
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Three people were in fair condition and eight were in good condition, CFD said.
The ambulances went to OSF Little Company of Mary Medical Center, University of Chicago Medical Center, St. Bernard Hospital and Jackson Park Hospital & Medical Center.
Video of the scene showed a No. 75 bus with some minor damage to its front end. A tan sedan had severe damage to its front end.
It was not immediately clear what led up to the crash or if any citations would be issued.
This is a developing story; check back with ABC7 Chicago for updates.