Teen dead after fall in Sydney building

A teenage boy has died in hospital from serious head injuries after falling down several storeys of a stairwell at Sydney's Queen Victoria Building.

The 13-year-old was taken to Sydney Children's Hospital in Randwick in a critical condition after falling down the four-storey stairwell on Sunday afternoon.

AAP understands he was sliding on a banister when the incident happened.

A report is being prepared for the coroner, a police spokeswoman said.