Chicago Fire Department officials said flames broke out at a townhouse on South King Drive near 93rd Street in West Chesterfield.
Fire crews rescued a woman in her 60s and brought her to a hospital after she was initially listed in grave condition.
The Cook County Medical Examiner later confirmed that the 66-year-old woman died from her injuries. Her identity was not yet known.
Neighbors told AB7 it wasn't the first fire in the building.
"They did bring someone out and she wasn't responding," nearby resident Cameron Williams said. "Actually, about a year ago, there was a fire that was across the hall... you can't replace a life with pictures, but everything else can be replaced."
Investigators are looking into the cause of the fire.
No further information was immediately available.