Auckland University of Technology is planning to cut at least 40 jobs at its Society and Culture faculty because of falling student numbers.

The university is the latest to express concern about declining interest in studying arts and humanities in New Zealand, which has led to a large budget shortfall at the faculty.

The Tertiary Education Union says the scale of the proposed cuts have shocked staff and it is urging the university to reconsider its plans.

A document sent to staff by the Faculty of Society and Culture dean Nigel Hemmington said full-time enrolments had fallen by 19 per cent – a total of 714 students - between 2012 and 2017.

The number of enrolled students in 2018 was also expected to be lower than forecast.

"This is disappointing as student numbers continue to decline and as a result, the faculty faces significant financial challenges in 2018 and 2019," Hemmington said.

The faculty has proposed reducing full-time employment positions by between 35 and 40, on a voluntary severance basis. The cuts amount to about 17 per cent of the faculty.

AUT noted that falling enrolments were mostly limited to the humanities. Overall, the university expected to grow by 600 students this year.

"Across the university sector in New Zealand and in many other countries, enrolments in the humanities and arts subjects have been declining over the past few years," a spokesman said. "Our Faculty of Culture & Society has not been immune."

Tertiary Education Union national industrial officer Irena Brorens said faculty staff were rattled by the proposals, which will affect both academic and administrative roles.

"People were surprised at the number of positions that were affected - quite shocked," she said.

"It is 40 full-time equivalent staff positions, so that's more than 40 people. That's a large number to be affected."

She said the union was hoping to minimise the number of job cuts in consultations over the next month. In the longer-term, the union wanted the Government to change the tertiary sector's funding model to allow more student places in the humanities.

Other institutions including the University of Otago and the University of Waikato have also reduced their number of arts and humanities staff in the last two years.

One of the factors in falling numbers of arts and humanities students is a perception that qualifications in these fields do not guarantee jobs after study.

Research by Universities New Zealand found 98 per cent of arts graduates were employed three years after graduating and 90 per cent of them were employed in a role which was related to their degree.

Faced with a shortfall of $2.5 million, AUT's Society and Culture faculty has already cut costs by not filling vacant positions, cutting non-essential travel, and reducing contestable grants for academic staff.

Despite those changes, it still had a $920,000 shortfall. By cutting 35 to 40 full-time positions, it expected to save $4 million.

The faculty aims for a ratio of one staff member for every 21 students. The ratio was 20.66 in 2012 and fell to 18.29 in 2017.