Up to 240 jobs are set to be lost at the Magellen Aerospace plant in Wrexham.
The company employs hundreds of people in north Wales and has sites in Wrexham and Deeside.
The company is an Airbus supplier and the redundancies will effect almost half of the current employees at the site.
Unite has described the news as devastating to the workers at the Llay plant and has warned of "huge" economic consequences for north east Wales.
Magellan Aerospace is a Canadian based company and warned it was "reviewing all its operations" during the Covid-19 pandemic.
The Canadian firm has released a statement citing the pandemic's "unprecedented impact on the aerospace industry."
Analysis by ITV Wales Work and Economy Correspondent, Carole Green
The news Magellan Aerospace is planning to cut 240 jobs at its Wrexham base is the latest blow to the Aerospace sector in Wales.
The company supplies the nearby Airbus wing plant at Broughton. Airbus has already announced it is cutting the number of planes it makes by a third as commercial airlines delay or cancel new orders for aircraft. 500 temporary agency staff have been let go at Broughton, another 3,200 are furloughed with redundancies looming.
These Magellan job losses are the knock on effect down the supply chain. This is a global industry feeling the effects of the Corona virus pandemic which has seen 2/3 of global commercial aircraft - approximately 20,000 planes grounded. Air travel has not experienced such a significant decline in passenger volumes since 9/11.
This is bitter news for the Magellan workforce and for the local economy. These are highly skilled well paid jobs in an area renown for its advanced manufacturing.
It follows other recent aerospace job losses in Wales: 142 at Timet in Waenarlwydd, Swansea and hundreds of British Airways maintenance jobs under threat at Llantrisant and Blackwood.
It’s a similar picture across the UK with 9,000 going at engine maker Rolls Royce and Airbus US rival Boeing cutting 16,000 jobs worldwide. Industry insiders say it will take at least three years for the sector to recover in Wales from the fallout of Covid and up to 8,000 jobs could go.