A neighbour, who was up for milking, saw a car coming down Easton Rd and turn into the property.
“About 30 seconds later I heard a big bang, some sort of gunshot,” she said.
Police found a critically wounded man lying beside his car shortly after 6am but he was unable to be revived and died soon after.
Detectives are believed to be investigating whether the death was drug-related.
It is also believed the father-of-two was the only person home at the time of the shooting.
A neighbour said he heard the sound of a car screeching about the same time.
“I’ve lived in Cohuna my whole life, so it’s a real shock," he said.
Another neighbour said the dead man had been living at the house for a couple of years.
“I would hear cars going to and from the house at all times of the night and they'd be going fast,” she said.
Police established a crime scene at number 32 Easton Rd near the intersection with Cohuna Island Rd and Melbourne-based Homicide Squad detectives arrived about midday, followed by crime scene officers who processed the scene for forensic evidence..
The death has shaken the tight-knit community, many of whom believe it was drug-related.
"There were some drug lords from Mildura here about six months ago looking for someone," a woman said.
"I wonder if that has anything to do with it?"
Melbourne's Andy Ellis and Mark Hatton said Cohuna's ambience and beauty had kept them coming to town every fortnight for the past 35 years.
"It's a little sleepy hollow. A quiet relaxing town. What's not to love?" he said.
"This is a terrible thing for a small community like Cohuna."