The teengager was shot in chest. A 20-year-old, shot in the shoulder, is listed in fair condition.
It happened about 7:30 p.m. at Ashland and Pratt in the Rogers Park neighborhood.
Police say they have gotten conflicting stories.
"When I looked out the window I can see the police coming up my street, and I heard the shots and came out. I figured out it was two kids, of course, it's becoming an epidemic. But I think it was more retaliation, 'cause mean, you just don't run up and shoot someone on the street," said Phillip Robinson, witness.
Neighbors say Ashland appears to be a dividing line for two rival gangs. Residents say the shooting is gang-related. Police say it is too early to determine that.
None of the injuries appears to be life-threatening.