Chicago firefighters responded to the 7800-block of South Rhodes Avenue at about 11:30 p.m., and found a 1.5-story, single-family home on fire, Chicago police and the fire department said.
The fire was struck out just before midnight, but a 50-year-old man had to be taken to University of Chicago Medical Center where he was pronounced dead, police and fire officials said.
The Cook County Medical Examiner identified the victim as Rawlin Brown. The medical examiner said Brown died of smoke and soot inhalation, and ruled the death an accident.
A family member said Brown leaves behind a wife and two children.
Family said the fire happened in Brown's mother's house, which he was cleaning because his mother had recently died. The family member said the fire happened overnight, when Brown was sleeping.
Brown worked as an engineer for ComEd and was a graduate of Bradley University.
No one else was injured in the blaze, the fire department said. The cause of the fire and the extent of the damage are still being investigated.
The Sun-Times Media Wire contributed to this report.