Fire crews battled the flames for more than two hours as some people were forced to evacuate and are now left in the cold.
There were at least six fire trucks seen at the scene at W. 23rd Street and S. Wentworth Avenue.
Chicago fire officials said the blaze broke out just after 8 p.m. in the rear of "Chang Ying Ginseng Hong," a Chinese herbal medicine shop that's been in this neighborhood for more than 30 years.
A neighbor who lives next door said the store was closed before the fire happened.
He described feeling the heat through his walls before rushing on his rooftop.
"When I went up, I feel the intensity of the heat. I saw the huge fire spring from the other building onto my building, almost onto the rooftop. So even though there is a wall in between, I feel the intensity of the heat," the neighbor said.
A firefighter was cut while battling the blaze, but is expected to be okay, fire officials said.
The cause of the fire is under investigation.