A pedestrian has been struck and killed as she tried to cross a road in northwest Victoria.

Police want to speak to anyone who saw the 46-year-old woman before she was struck by a Holden sedan travelling east in Monash Avenue in Nyah West at 9.15pm (AEDT) on Friday.

Investigators believe the woman, who died at the scene, had been trying to cross the road.

The Holden driver, a 21-year-old Nyah West man, stopped at the scene.

He was uninjured but treated for shock.

Police are seeking witnesses, particularly the drivers of a large header harvesting machine and a ute seen travelling west shortly before the collision.

The crash brings the state road toll to 249, three more than this time last year.