Police said the victim was found unresponsive with a head injury inside a South Shore residence in the 6900-block of South Oglesby Avenue around noon.
The victim, whose gender was not immediately known, was pronounced dead on the scene, police said.
Police said a person of interest was taken into custody and charges are pending.
Area One detectives are investigating.
Police did not immediately provide further information.
INTERACTIVE SAFETY TRACKER Track crime and safety in your neighborhood