Chicago police said the incident occurred just after 11:20 p.m. as Kenneth Paterimos and a 30-year-old man were leaving Richard's Bar, which is in the 400-block of North Milwaukee Avenue.
The pair got in an argument, and the 30-year-old man stabbed Paterimos several times in the arm, neck and back. The 23-year-old was taken to Stroger Hospital, where he later died.
The 30-year-old suspect was seen lying on the ground, handcuffed outside the bar. He was taken into custody, and charges are pending, police said. A knife was found on the scene.
The suspect had not been identified early Saturday.