The Canberra institution raked in $320 million in fees from both onshore and onshore international students last year, an increase of 26 per cent on the previous year's takings.

In the same period, the number of international students studying at the university rose by 17 per cent to 10,623.

That takes the proportion of overseas students to two out of every five people enrolled at ANU.

The uptick helped push the university's revenue to $1.375 billion, up from $1.256 billion in 2017.

The fees from international students far outstripped the money recouped through HECS-HELP student payments, which rose to $91.4 million in 2018 from $86.9 million in 2017.

It also outpaced revenue from fee-paying domestic postgraduate students, which fell by 56 per cent to $4.2 million in 2018.

The figures are contained in the university's 2018 annual report, tabled in Federal Parliament last week.

The report said: "the strong growth in international student numbers and revenue ... led the ANU Vice-Chancellor, Professor Brian Schmidt AC, to announce late in 2018 that the university would be capping further growth in international student numbers".

It is the first time the university has acknowledged the change in policy amounts to a cap on a particular segment of the student population.

An ANU spokesman stressed that the admissions criteria had changed for both international and domestic students, in order to halt the growth of the university.

"ANU has made a decision about the size of its student population driven by the university's long-term vision and the type of education experience we want to provide," he said.

"We do not aspire to have a larger student community than we currently do, which is around 20,000. Many of our students are able to live on campus, and we plan to keep that special part of the ANU character."

It would be achieved by introducing a new competitive ranking process to identify the very best students from Australia and overseas, and requiring all applicants to pass an English language test.

Most of ANU's international cohort came from North-East Asia.

Seventy-five per cent of overseas scholars came from this region, which includes China, Japan, Taiwan, Mongolia, North Korea and South Korea.

In 2016, students from that region accounted for 67 per cent of international students.

Despite this, the spokesman said the cap was not expected to hurt the university's bottom line.

"The government's key higher education regulator, TEQSA, has verified that the University is in strong financial health," the spokesman said.

"Like most Australian universities, all our revenue, including fees from international students, helps support delivery of our mission.

"ANU is a research-intensive university and continues to secure half of its revenue from high-quality research and research support."

The report comes after an analysis from the Organisation for Economic Co-operation and Development showed Australia's higher education sector was far more reliant on international students than other countries.

International students represented around 48 per cent of those enrolled in masters degrees, and about 32 per cent of enrolments in doctoral programs in Australian institutions.

However the number of international students at the ACT's other major university, the University of Canberra, has fallen.

Its 2018 annual report - tabled in the ACT Legislative Assembly in May - showed the number of international students actually fallen - from 2422 in 2014 to 2165 in 2018.

That means 19 per cent of students - or one in five - hailed from overseas.

In its report, the university said it faced challenges growing its population of international students while located outside of the major cities.

However it still increased its revenue from international students in 2018 to $56.7 million - up from $50.2 million in 2017.

The university is also far less dependent on international student revenue than ANU.

It made more from HECS-HELP and other student loans - $68.9 million in 2018.

The University of Canberra's Pro Vice-Chancellor (Students, Partnerships and International) Lawrence Pratchett said the university maintained a focus on "quality over quantity" in international student recruitment and retention.

"As the University for Canberra, we are dedicated to serving domestic students in our own backyard as well as offering international students the opportunity to experience our city," Professor Pratchett said.

"We offer a different product from our ANU counterparts and, therefore, it is difficult to compare apples and oranges, but we continue to invest in both domestic and international student opportunities, including scholarships, to ensure a high-quality level of education is met."