Authorities said the attack happened early Monday morning on Buford Highway.
Three men broke into a home at the Dover Station Apartments that had nine people, including five children. The assailants used a handgun to beat one man, who was recovering from his injuries.
A second man in the apartment was hit on the head. He was taken to Grady Memorial Hospital in Atlanta and listed in critical condition.
Police tell WSB-TV that the gunmen may have gone into the apartment looking for drugs, but they targeted the wrong place. Investigators are still searching for the suspects.