NATFHE general secretary Paul Mackney is to write to Education and Employment Secretary David Blunkett, protesting at the redundancies, and the union may organise a national day of action in support of the sacked lecturers.
Staff at Cricklade will be balloted early next month over possible industrial action.
The college, under investigation for its links with IT training company Extras Ltd and claims made on the European Social Fund, suspended principal Richard Evans in March this year following a highly critical report from the Further Education Funding Council.
Acting principal Elizabeth Blakemore denies the sackings are victimisation.
Paul Mackney said: "If union activists can be railroaded out of their jobs on the whim of their employers, ordinary lecturers will feel that they don't stand a chance."