The Celestica electronics factory in Swords, North Dublin, is to close with the loss of 250 jobs.
The Canadian company blamed its decision on the continuing downturn in the telecommunications market.
Phone companies, laden with debt, are investing less in new equipment and the manufacturing of this equipment is moving to cheaper locations.
Celestica made printed circuit boards in Dublin. It now plans to move this production to other Celestica factories overseas.
Celestica once employed almost 1,000 people at its factory in Swords but has been cutting its workforce since 2001. It has twice cut its workforce here and when it closes, 250 permanent jobs and 70 temporary jobs will be lost.
Workers who were informed of the decision today will receive six weeks' pay per year of service. The factory will close over three to six months.
The Tánaiste and Minister for Enterprise, Trade & Employment, Mary Harney, described the job losses as a shocking blow for the workforce and the local community.
But she said a number of other companies were already recruiting aggressively in North Dublin.
'I am very confident that within a week or so I will have good news for North Dublin that will help to ease the burden for many of those affected by today's announcement,' she added.
