Fears have been raised about the future of the Pfaudler Balfour manufacturing plant in Leven.
GMB trade union said 100 Fife jobs could be lost if the global technology firm decides to consolidate its operations in Germany.
It has called on the Scottish Government to intervene and protect the workforce.
But Pfaudler Balfour, which supplies chemical companies and also has a plant in the German town of Schwetzingen, has rejected GMB’s claims, maintaining there are no closure plans.
GMB Scotland secretary Gary Smith said: “GMB Scotland has been informed that the company considers that its market supplying equipment to the pharmaceutical industry does not favour keeping two plants open.
“It is considering whether it should consolidate investment in a single plant.
“GMB Scotland is concerned that at a main board meeting in Germany later this week a decision could be made to consolidate into a single plant and that there is a real possibility that the investment will be made in Germany and not Scotland.
“We have a real fear that the workers in Scotland will be fired because they’re cheaper and they have fewer redundancy rights. German unions will be presenting a case on Wednesday about the future of their plant.
“The Scottish Government should seek an immediate meeting with company management before the board meeting to ascertain what the company’s plans are and how the Government can assist in keeping this long- established plant in Scotland.
“Manufacturing jobs are being hammered in Fife. Fife Joinery closed late last year, the BiFab yard is on its knees and now this plant is under threat. The Scottish Government has to act to stop this carnage of jobs.”
It is understood Pfaudler Balfour is considering restructuring options for its European operations.
When contacted by The Courier, the firm made no comment other than to reject GMB’s claims and say no decisions had been made.
Councillor Tom Adams, who chairs Levenmouth area committee, said the loss of Pfaudler Balfour would be a “devastating blow” for the area.
He said: “It’s a well established and well respected company. Everybody knows somebody who has worked there.
“We would want to make sure the investment is made here as opposed to Germany.”
A Scottish Government spokesman said: “We appreciate this will be an anxious time for the workforce at Pfaudler Ltd in Leven, and for their families and the local community.”
He added: “Scottish Enterprise is working closely with the company and is meeting with the management team to look at all possible options for supporting the business and safeguarding Scottish jobs.
“Ministers are watching the situation closely.”