Police and emergency services are currently on the scene of a fatal crash in Charlton.
Investigators believe the vehicle was travelling along the Calder Highway when the driver lost control and crashed into a tree about 1.15pm.
The white Toyota has then rolled as a result of the impact with the tree.
The driver and sole occupant of the vehicle, who is yet to be identified has died at the scene.
The exact circumstances surrounding the crash are yet to be established and the investigation is ongoing.
The Calder Highway is closed between Burong Highway and St Arnurd-Wycheproof Road until further notice.
Anyone with information or who may have witnessed the incident is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au