Investigators said it happened at around 10:27 p.m. at Humboldt Deli and Liquors in the 2900 Block of W. North Avenue
Two armed men exchanged gunfire with the 45-year-old victim, according to police.
He was shot in the left arm and taken to Stroger Hospital in fair condition, police said.
There is no one in custody.
The circumstances surrounding the incident are being investigated by Area Five detectives.