Hakeem Pickering-Smith, aged 15, is in intensive care at the Royal Hallamshire Hospital after he was struck by a car on Catch Bar Lane, Hillsborough.
The Forge Valley School pupil was hit by a gold Fiat Punto on Sunday night.
He suffered life-threatening injuries in the crash, which happened close to the junction with Leppings Lane, at 9.30pm.
An investigation into the collision is underway.
Anyone with information should call South Yorkshire Police on 101.