Emergency services were scrambled to the incident in Tiverton at around 8am this morning.
The driver, 54, had reportedly suffered a medical episode and fallen from the door to the bus.
An air ambulance was scrambled to a nearby Tesco supermarket car park as medics tried to save the man.
But he was tragically pronounced dead at the scene.
A police spokesperson said: “We were called to reports of a male who collapsed in the street.
“He was a bus driver for Stagecoach and was 54 years old. It is believed he died of natural causes.
“He may potentially have fallen from the bus and hit his head but that is unconfirmed at this time.”
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