Hundreds of workers at Alexander Dennis in Camelon are striking in a dispute over pay.
Members of trade union Unite rejected a 4.5% pay offer.
Around 400 people are employed at the factory.
The action will last for two weeks.
An offer, which would increase their wages by 4.5%, was turned down by the union.
Sharon Graham Unite general secretary said: “Unite members at Alexander Dennis are being forced to strike again in their fight for fair pay. Our members remain utterly determined to get a fair offer from the company.
“We will back our members all the way in their fight for better jobs, pay and conditions.”
Pat Egan, Unite industrial officer said; “The two-week long strike action will be the first in a series of lengthy stoppages to hit the Camelon factory. Our members are not asking for the earth but simply an offer worthy of their hard work and loyalty. Alexander Dennis have instead made penny pinching offers which amount to a real terms pay cut. This is unacceptable and our members will continue to fight until they get what they deserve.”
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