It was an early morning for emergency services in Myrtleford on Tuesday as the engine of a gas transportation truck caught fire, just after 1am, south east of the township on the Great Alpine Road.

While the load was not compromised, the truck's engine and cabin was extensively damaged by fire.

The driver was uninjured and able to escape, before the fire took hold.

Myrtleford CFA captain, Gloria Pizzolitto, said the travelling truck driver was having his rest break, asleep in the cabin of the vehicle, when he was awoken by a sound.

Sergeant Cam Miller of Myrtleford police said the prime mover was destroyed.

"At this stage, the cause of the fire seems to be a mechanical fault," he said.