A 41-year-old man was critically injured when he was hit by a car in Kellyville last night.
Police said the Blacktown man was crossing Memorial Avenue, Kellyville when he was struck by a Nissan Tida hatchback that was travelling east at about 9.15pm.
Police said he has significant head and internal injuries.
The injured man was taken to Westmead Hospital for emergency surgery and remains in a critical condition.
The driver of the Nissan, a 59-year-old Kenthurst woman, stopped at the scene and has assisted investigators.
Anyone who was in the area at the time and might have witnessed the incident is urged by police to come forward.
Anyone with information: call Castle Hill Police Station or Crime Stoppers on 1800 333 000.