The 10-year-old boy was struck by a Mercedes SUV as he was crossing North Liverpool Road in Mount Pritchard.
Police rushed to the scene at 8.40am following the incident.
9News understands the boy’s sister tried to pull him back from the road as the car approached, but it was too late.
He suffered severe injuries to his head and several broken bones and was taken to Westmead Children’s Hospital in a critical condition.
NSW Police Inspector Joe Ibrahim said the scene of the crash was “challenging” for attending crews.
“These things are horrific when happen to anyone but particularly children,” he said.
The driver, a 35-year-old woman, was taken to hospital for mandatory testing.
Investigators are looking into how fast she was going at the time of the crash.
Police are investigating.
