Police have charged a woman with four breaches of a family violence order after she allegedly struck and killed a man with a car in southern Tasmania.

Police were called to Wilmot Road in Huonville, outside Huonville High School, just before 1:30am on Saturday.

The 26-year-old man from the Huon Valley died before emergency services arrived.

The 34-year-old woman, who is from Lucaston, was taken into custody at the scene.

"The male and the female were known to each other. So the relationship between them will be subject to scrutiny and form part of the investigation," Detective Inspector Michael Smith said.

"Any causative factors we're not sure of yet … but that will form part of the investigation."

Nearby residents and people known to the deceased man were responsible for alerting police and ambulance.

The woman will appear in the Hobart Magistrates Court on Sunday.