A woman is in a critical condition in a Melbourne hospital after falling from a moving ute in western Victoria.

Police said the woman, aged in her 60s, sustained life-threatening injuries during the incident in Bulgana, near Stawell on Friday evening.

Police were told the woman was in the back of the ute as it was driving on a private property.

The woman was airlifted to The Alfred hospital in a critical condition.

The 45-year-old male driver was arrested at the scene and remains in custody. He has been assisting police with their enquiries.

Major Collision Investigation Unit detectives were en route to the scene to investigate the incident.

• In Pictures: Christmas around the world
• Boxing Day sales top $2 billlion
• PM remembers Indonesian tsunami victims