The Australian National University has climbed into the world's top 20 universities and strengthened its position as Australia's top-ranked university.

The latest QS World University Rankings for 2015-16 rated ANU as equal 19th in the world, up from 25 last year, and among the world's great research and education institutions including Oxford, Cambridge and the great Ivy League universities in the United States.

The QS World University Rankings named ANU as the number one institution in Australia, based on a range of measures such as academic reputation, employer reputation, research citations and the ratio of staff to students.

"While rankings can move around from year to year, the latest results are a great endorsement of the hard work and commitment of our staff and students, who all contribute to make ANU one of best places in the world to study and conduct research," said ANU Vice-Chancellor Professor Ian Young AO.

"ANU is committed to excellence, and continues to strive to deliver research and education that is equal to or better than any on offer in the world.

"Every day our staff and students work to improve our understanding of the world and solve the problems that confront societies."

Globally, ANU was ranked 12th in the world for Arts and Humanities, 18th for Social Sciences and Management, and equal 20th in the world for Natural Sciences.

ANU was ranked 26th in the world for academic reputation, with an overall score of 99.6 out of 100.

In Australia, ANU was ranked first in Arts and Humanities and Natural Sciences, and second in Social Science and Management.

More than 3,500 Universities were considered by QS, with more than 120,000 academic staff and employers surveyed worldwide.