Members of the University and College Union and Unison will walk out on 4 June as part of a dispute over plans for up to 165 jobs to be axed across the university.
It will be the second time that UCU members have walked out in protest at the cuts, following a one-day strike on 21 May.
The proposed job losses – which equate to about 10 per cent of London Met’s workforce – follow a fall in recruitment for the second consecutive year and a review of the university’s staff costs.
London Met’s vice-chancellor John Raftery, who took charge of the institution in August, has said the “the university’s cost structure is too high for an institution of its size and income”.
Two-thirds of UCU members who took part in the ballot at the north London university voted "yes" to strike action over the job losses. About three-quarters (78 per cent) of Unison members who voted backed strike action.
Staff will be on picket lines on 4 June from 8.30am at all the main entrances to the university, including Holloway Road, Moorgate and Aldgate, with a rally taking place outside the former Women’s Library, in Aldgate, at noon.
Barry Jones, UCU regional official, said that it was “disappointing that the university is still refusing to budge over these proposed cuts”.
“Instead of cutting back on jobs the university should be building on its reputation for expanding access to education,” said Mr Jones.
“Strike action is always a last resort, but in order to avoid further disruption, the university needs to urgently reassess its plans and sit down again with the unions to negotiate a better way forward,” he added.
A London Met spokesman said it had commissioned a report to review the size and shape of London Met, which had shown that its cost structure was “too large for a university of our size".
“We therefore need to reduce our cost structure to be more in line with our student numbers, as well as universities in the capital similar to London Met,” he said.
London Met had engaged fully with staff unions to try to avoid the need for compulsory redundancies, he added.
“Our priority as a university is in supporting our 14,000 students, and we have contingencies in place to minimise disruption to them during any strike action,” he added.