Two fire engines from Morecambe and Lancaster were called out to Morecambe Road following reports of "black smoke" coming from the engine compartment of the bus, say fire crews.
Firefighters arrived at around at around 8pmto find the bus well alight.
A spokesman for the fire service said: "Two fire engines and crews, from Morecambe and Lancaster, responded to the report of black smoke coming from the engine compartment of a bus.
"Anyone on the bus had got off safely and firefighters used two hosereel jets to extinguish the fire then used a thermal imaging camera to ensure that there were no remaining smouldering pockets of fire."
Nobody was injured during the incident.
Correction: We earlier reported that passengers were on the bus. We would like to correct this to say that no passengers were on the bus at the time of the fire.