Workers at Fujitsu are to vote on industrial action over pay and pensions.
The IT company employs 160 people at offices at Timber quay in Londonderry and around 14,500 UK-wide.
The union Unite said that proposed changes to the pension scheme would reduce worker's take home pay by at least 15%.
In May, the company announced that it would be closing its final salary pension scheme.
The move would effect 4,000 of the current workforce who are members of the scheme.