University College Birmingham (UCB) is planning to get rid of 73 staff and hire 42 new staff on cheaper contracts, according to the University and College Union (UCU).
The union says the cuts would threaten teaching in the schools of business, tourism and creative industries; and health, sport and food.
It says it is prepared to take legal action to stop the cuts going through, claiming the move flouts the law on consultation.
The university said the union had not given an accurate picture of the situation and that a smaller number of redundancies were planned.
UCU regional official, Anne O’Sullivan, said: "It is shocking that University College Birmingham is so committed to slashing student provision it is willing to risk legal action.
"Proposals to cut 73 senior staff and create 42 new roles with non-negotiated changes to the pay and grading structure are a clear breach of the university’s legal obligations.
"Losing 73 senior lecturers in two schools would be a disaster for students. UCU will fight these proposals.
"We are calling on the university to meet with us to find a solution that protects jobs and student learning before it is forced to defend itself in court."
The union says that many of the at risk jobs involved staff who had been at the university for more than 20 years, while 42 the new posts would see staff saddled with increased workloads.
A UCB spokesman said: "The comments from UCU are a not an accurate picture of what’s happening at UCB.
"We are currently in the process of changing structures in our academic teams, in the same way as many other colleges and universities are re-evaluating their departments.
"This is in response to changing government policy, a rapidly-changing further and higher education landscape, and the impact of Covid.
"The changes are imperative to allow us to realign and modernise the curriculum, and ensure our students receive the most up to date teaching and learning experience.
"As with any restructuring, this does come with some changes, and as a consequence a number of staff roles are at risk of redundancy.
"The numbers involved are smaller than those quoted by UCU, and we anticipate that many will be suitable for alternative roles in the new structure.
"There are no changes to staff terms and conditions, and all jobs being created are on the agreed academic pay spines. We have never invested more in staff and student facilities, and we are not reducing our provision for students."