The boy was shot in his leg in Spital Lane, off Spital Hill, Burngreave, in the early hours of yesterday morning.
Emergency services were alerted to the gun attack at 12.10am and the injured boy was taken to hospital but he has since been discharged.
His attacker remains at large.
The crime scene was cordoned off yesterday while forensic experts examined the area and officers attempted to piece together the circumstances surrounding the shooting.
Witnesses are urged to come forward.
Anyone with information should call South Yorkshire Police on 101 and quote incident number 7 of May 19.
Crimestoppers can also be contacted, anonymously, on 0800 555111