The number of new Chinese students coming to New Zealand fell 20 percent in the 12 months to the end of June, cutting millions of dollars from education providers' income.
Immigration New Zealand figures show 8604 first-time Chinese students got study visas, down from 10,534 in the preceding 12-month period.
China is New Zealand's single most important source of foreign students and the fall in new visas issued to students from that country is the first since 2013.
An education agent with the company Leader Investment Group, Jean Hu, said the government's planned changes to immigration and work policies for foreign students were to blame.
"That's because the immigration policy [has] tightened up, especially for the skilled migrant category and probably in the future, the open work visa for the new-graduate students," she said.
"The Chinese students coming to New Zealand, the most attractive policy for them is to get New Zealand residency in the future," Ms Hu said.
Canges signalled by the government would prompt many Chinese students to look to other countries such as Australia and the UK, Ms Hu said.
The total number of Chinese students in New Zealand could fall by "30 percent at the least", she said.
The Minister of Immigration, Iain Lees-Galloway, said the fall in new Chinese students was unlikely to be due to the government's plans.
"It is hard to say exactly what is driving this at this stage, but I think it is a very tenuous link to suggest that upcoming changes that haven't come into effect yet are driving this," he said.
The government's plans could increase the number of Chinese students, Mr Lees-Galloway said.
"The fact that we are offering more open work rights for people who choose to study at a higher level, which is what overwhelmingly Chinese students do choose to do, then that may result in more Chinese students choosing New Zealand," he said.
The deputy chief executive of Education New Zealand, John Goulter, said the fall began in the middle of last year and was focused on private tertiary institutions, English language schools, and schools, while universities had more new enrolments from China.
"Those sort of factors lead us to think that maybe it's a reflection of changing China local demographics," he said.
"Maybe more and more students coming to New Zealand from China are wanting a different level of qualifications rather than the foundation ones that they had been doing previously."
Mr Goulter said due to the pipeline effect of growth in new enrolments in previous years, the total number of Chinese students had not fallen.
Education New Zealand expected China to remain a strong source of students for New Zealand, he said.
"We expect that market to be stable or indeed to grow slightly over coming years so we'd be surprised if it was a longer term turnaround," he said.
The executive director of the Schools International Business Association, John van der Zwan, said the drop in new visas from China was affecting secondary schools in Auckland more than other areas.
He said a range of factors were behind the change including an increasing number of international schools in China and schools set up by foreign providers specifically for Chinese students.
"There are more options for Chinese students to stay in China and get a different type of education," he said.
Mr van der Zwan said primary schools were bucking the trend and enjoying an increase in new enrolments from China and overall the number of foreign students in schools this year had not fallen.
However, he said another year of decline in new students from China would be a worry.
"That is a concern and I think there's enough indicators across the industry as a whole that China is one that we need to watch carefully and this may well be the beginning of something that we need to look at more closely in the future. So it is something that we're monitoring."