Unite union said 87% of its members at Fujitsu had voted in favour of striking in a consultative ballot, which could now pave the way for industrial action.
Unite said proposals to close the pension scheme could reduce the total pay of each employee by at least 15%.
Fujitsu’s final salary pension scheme was closed to new members in 2000, and the proposed closure of the scheme will be under consultation until 25 September.
Peter Skyte, Unite’s national officer for technology, said: “Fujitsu Services is not struggling or failing. It is a highly profitable and successful company but one which is seeking to take advantage of the recession to attack jobs, pay, pensions and conditions.”
Last week Fujitsu announced that it would cut 1,200 jobs – 10% of its UK workforce – and enforce a pay freeze.