Staff and students attacked Leeds University this week over proposals to close the School of Continuing Education as a result of a £250,000 deficit.
The school, which opened in 1946 and takes 3,500 mostly local students a year, is facing serious financial problems.
The senate was due to vote this week on plans to scrap the school in favour of a new centre for part-time education.
But staff said the plans could undermine Leeds' commitment to adult learners in the region and would dissolve existing structures of expertise because the centre would be spread across nine faculties without academic leadership.
"The school has financial difficulties and all staff recognise that these need to be resolved," said Malcolm Chase, the head of school. "But in the light of the increasing emphasis on widening participation and on the regional roles of universities, we fear that the proposals will damage opportunities for part-time and mature students, and will have an adverse effect on research and development in adult education and lifelong learning."
Dr Chase said the school made £1.4 million in research income last year and blamed the deficit on the extra costs of teaching non-traditional learners.
The Association of University Teachers said its members had been assured by the university last year that the school was safe. "Now we hear it is to close, and we want a full consultation because they have reneged on their word," an AUT spokesman said.
Richard Coomber, 58, who is studying part time for a degree in local history, said students would continue to protest at the closure plans. "My class is up in arms at the news," he said.
"We have been given no information from the university about the future of our courses and everything is up in the air. Apart from my anxiety about my own course, I feel there is a principle at stake here at a time when the government is promoting lifelong learning."
A university spokesperson said: "We remain committed to providing part-time learning opportunities for students of all ages and backgrounds in the region. All students in the school will be able to complete their courses.
Part-time teaching will continue in discipline-specific departments rather than through the School of Continuing Education."