A 33-year-old man is in a serious condition in hospital after being stabbed in the stomach and neck at a bar in Sydney's west.


Police said officers were called to Rooty Hill just before 10pm on Sunday to find the man outside the premises with multiple stab wounds.


He was treated at the scene by ambulance paramedics and taken to Westmead Hospital in a serious condition.


Police have appealed for any witnesses to come forward and would like to speak to the driver of a white sedan seen leaving the area shortly after the incident.


AAP