Officers from Lake Macquarie police district have been told the five-year-old boy was bitten on the left side of his neck by the family dog at their Lake Macquarie home, near Newcastle, on Sunday afternoon.

The child was treated at the scene by paramedics and the Wetspac Rescue Helicopter critical care team before being airlifted to The Children's Hospital at Westmead.

The boy was in a stable condition.

Police have been told the two-year-old dog - described as a Rottweiler-type breed - is to be euthanised.

Inquiries are continuing.