Chinese students are being promised a "guaranteed pathway" to gaining New Zealand residence by agents in the mainland who charge up to $24,000 to cheat on their behalf.
For the fee, students need to provide only their passports and photographs, and the agents will do the rest - including supplying fake documents and certificates to support the application.
Immigration New Zealand is seeking more information on this possible immigration fraud, and said it will "investigate and prosecute if appropriate".
One in five international students gained permanent residence within five years, and the agency says they are "an important source of skilled migrants for New Zealand".
Immigration said it was aware of "cases where unscrupulous immigration agents have misrepresented clients' interest", and this has resulted in ongoing investigations into visas which may have been obtained fraudulently.
A spokesman for the agency said it had not received any complaints or allegations relating to the "guaranteed pathway" scheme, and would welcome any information about it.
Sixty-four permanent residence visas had been revoked in the past 12 months, 14 of which were former international students.
"None of the 14 student visa holders who had their residency revoked are facing immediate deportation, all have cases before the Immigration and Protection Tribunal and we are awaiting the outcomes of these cases before determining further action," the spokesman said.
One former student, who has her case before the tribunal, said she did not know her agent had included fake documents to support her application for residence.
The woman, originally from Shanghai, and married to a New Zealand resident, has appointed an Auckland-based licensed immigration agent to represent her in her appeal.
Another, who spoke on the condition of anonymity, said he did not know the scheme was "against the law".
"In China, a lot of things get done because of guanxi [relationship], and I thought the reason we are paying such high fees is because they have a good guanxi with immigration authorities here," he said. "I did not see what they added to my application, but was shocked to learn that they had added a university degree when I had only completed high school education."
He would not name the agent that he paid about $18,000 for the "guaranteed" application service, but said the agent was introduced to him by friends of his family in China. Nearly 75,000 international students were approved to study here last year with China being the largest source country.
Arron Baker, acting general manager for immigration, said any person who obtained a visa dishonestly risked prosecution and having their immigration status reviewed with a view to being deported. He said improved identity management, and the use of an international fingerprinting checking system and biometric information sharing had yielded "excellent results".
"Since January last year, about 440 people have been checked using this system.
"Of these, 101 matches were received including people who were matched by more than one country," Mr Baker said. "Thirty-seven matches were able to provide vital identity fraud information, concealed criminal history or immigration fraud intelligence to Immigration."