Warrnambool police Sergeant Tom Morris said the driver was heading west in the Iveco truck on the Hopkins Highway near Purnim when the vehicle drifted onto the left-hand-side of the road.

"He's overcorrected and ended up facing east. The truck flipped, rolled and landed back on its wheels among large trees," he said.

"The accident happened at 1.50am. The driver was taken to the Warrnambool Base Hospital with minor injuries."

It's suspected the truck, which was empty at the time of the accident, will be an insurance write-off.

Sergeant Morris said investigations into the cause of the accident were continuing.

"The truck remains at the accident scene, but it's well off the road and traffic is unimpeded," he said.

"Warrnambool highway patrol unit police officers will be attending this morning at the accident scene to take measurements," he said.