According to the Chicago Fire Department, all four were taken to local hospitals in serious to critical condition. They have been stabilized.
The drive-by shooting happened Monday evening in the 9400-block of South Justine Street.
Police say the gunman opened fire on the four males as they walked down the sidewalk.
A 15-year-old was shot in the abdomen, and a 17-year-old was shot in the chest, according to authorities.
Two others, 17 and 19, were shot multiple times.
In a separate incident on Christmas Eve, a 19-year-old was shot on the West Side.
Two other shootings took place in the Gresham neighborhood.
"It's just pure madness... It's a shame it would happen on Christmas Eve when families are supposed to be together. It's madness," said Andrew Holmes, community activist.
