Staff will walk out at Cardiff and Bangor in a row over pay and conditions.
Staff at Welsh universities are among those taking strike action today.
The University and College Union is locked in a dispute over pay, conditions and pensions.
Members will walk out at 60 universities across the UK including Cardiff, Bangor and University of Wales.
Those going on strike include lecturers, librarians, technicians and student support staff.
Employers insist they'll do all they can to make sure the strikes don't 'impact badly on students'.