Auckland met the requirement after AUT University entered the university rankings for the first time in September, along with the University of Auckland.
"With AUT's inclusion this year, Auckland rightly deserves its position in the top 50 list," said QS head of research Ben Sowter.
"The city's strengths clearly lie in its high quality of living, scoring 91 out of a possible 100 points, student mix at 84 points and employer activity at 79 points."
Other cities that have also made it to the top 50 list for the first time include Oslo (48) and Prague (45).
No other New Zealand cities have two tertiary institutions on the top 500 list.
AUT University Vice Chancellor Derek McCormack said: "Auckland is a great city for students, both Kiwi and international, and we are delighted that our success is helping to promote that."
Professor McCormack said AUT would have surprised "a few people" when it made the QS list last year just 12 years after becoming a university.
"Being ranked does make AUT and Auckland City an attractive prospect as international rankings are important especially for off-shore students when weighing up their study options," he said.
Auckland Mayor Len Brown said Auckland's ranking was a recognition of the city's growing significance as an international destination for students.
"The effort we are putting into areas such as transforming our city centre and upgrading transport infrastructure across Auckland can only add to our international reputation as a great student city," the mayor added.
And the top student cities are:
1. Paris
2. London
3. Singapore
4. Sydney
= 5.Melbourne
= 5. Zurich
7. Hong Kong
8. Boston
9. Montreal
10. Munich
18. Auckland
(source: Quacquarelli Symonds Best Student Cities)