Sheffield Children's Hospital is one of three hospitals which have failed fire safety checks.
The fire safety checks were ordered in the aftermath of the Grenfell Tower fire.
Buildings at London's King's College Hospital and North Middlesex Trust have also been found to have combustible cladding.
The hospital said the cladding is on the top two storeys of the Shephenson Wing on Western Bank but is not an area where patients stay.
More to follow.