About 1:25 p.m., the men, 33 and 28, were in the 11800 block of South Emerald Avenue, when two people walked up to them and fired shots, police said.
The 28-year-old was struck in the head, and the older man was struck in the head, chest and rear, police said. They were pronounced dead at the scene, but were later taken to Roseland Community Hospital.
They have not yet been identified.
Chicago police continue to investigate.