HP is set to axe 850 manufacturing jobs in the UK, according to trade union Unite.
The cuts are part of 5,700 European layoffs newly announced by HP.
The union branded the British job cuts "yet another devastating blow" for UK manufacturing jobs.
The HP staff affected work at Renfrewshire in Scotland, and produce storage devices and servers. That production will now be moved to the Czech Republic, the union said.
Some 500 technical and administrative jobs are expected to remain at the plant, originally opened by Compaq in 1987.
HP declined to elaborate, other than to say it "reviews its businesses and markets to ensure they continue to offer the best possible value to our customers, and to ensure that they are aligned to our growth plans and company objectives".
HP previously announced that it is cutting its global workforce of 320,000 by two percent, and has imposed a five percent pay cut for staff.
Unite Scottish regional secretary John Quigley called the Scottish jobs announcement "yet another devastating blow in a long line of tragedies for UK manufacturing".
"When over £900 billion of public funds can be poured into bailing out the banks, it is utterly unacceptable that help cannot be directed into a sector that is fundamental to nurturing our economic revival," he said.
"It is now up to those in power who have neglected this sector for so long to wake-up before it is too late."
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