Police said the shooting happened in the South Chicago neighborhood's 8000 block of South Phillips Avenue at about 7:15 p.m.
An 18-year-old man was on the sidewalk when someone shot him in his head, police said. The victim was transported to the University of Chicago Hospital in critical condition.
Two detectives are investigating.
Police did not immediately provide further information about the shooting.
INTERACTIVE SAFETY TRACKER Track crime and safety in your neighborhood