A woman has died after a tree fell onto a car north west of Melbourne.

It happened while the four-wheel drive was travelling along a sealed road in the Macedon ranges at Woodend just after 2.30pm on Thursday.

The passenger died at the scene and the driver suffered non-life threatening injuries.

He has been taken to hospital for assessment.

SES workers were at the scene for hours to clear the wreckage.

Authorities are investigating the cause of the accident and have asked anyone with dashcam footage to come forward.

-AAP