New Zealand is becoming a popular destination for retiring Chinese, with more than 1200 over-50s relocating here in the past year and numbers rising fast.

Despite an effort to attract the rich, skilled workers and students from China, the only rise in numbers for Chinese migrants are those who came through the family categories.

The increase has led to fears that elderly Chinese, many of whom cannot speak English and do not work, could end up straining services here.

For the third consecutive year, China has topped Immigration NZ's parent and sibling/adult child stream, with 1632, and a further 1264 others qualifying through the parent policy.

"China was the largest source country of residence approvals through the parent policy in 2009-10 ... The proportion of parent-policy approvals from China increased from 25 per cent in 2007-08 to 37 per cent in 2009-10," the Department of Labour said in its latest annual migration trends and outlook report.

"China accounted for more than one-third of residence approvals in the parent and sibling/adult stream ... up 16 per cent from the previous year."

A total of 1289 mainland Chinese who gained residency last year were aged 50 and over.

Over the same period, the number of students from China continued to slide, from a peak of 41,510 in 2003 to 14,998.

Work visa approvals also dropped from 15,294 in 2008 to 10,866 last year.

Licensed immigration adviser Jimmy Lee says that having too many elderly Chinese migrants here "could end up a liability" for the country.

"Most of them cannot speak English, are unable to get a job and are dependent on their children to support them," said Mr Lee, who heads the immigration division at Alex Lee Lawyers.

"They will not be able to contribute much economically, but could add a strain to our health and support services."

Asian studies professor Manying Ip, of Auckland University, has warned that if the trend continues, it would bring new health, housing and socio-economic challenges.

Immigration researcher Professor Paul Spoonley says the Chinese trend was not unexpected.

"New Zealand has had a period of skill recruitment, and now we've got a period of family relocation," he said.

"Once a migrant spends a few years here and becomes established, then they start looking at bringing their parents over. With China's one-child family policy, it's going to be more impacted by that than most other immigrant sources."

Nearly every new resident from China is able to sponsor his or her parents to live in New Zealand permanently because of China's one-child policy and Immigration NZ's "centre of gravity" rule, which allows parents to be sponsored if they have half or more of their children living here.

Professor Spoonley said many Chinese moved here so that they could have more than one child and wanted their parents here to help with raising their children.

He said the adverse economic conditions globally had dampened overall migration movements, which explained why Chinese migration numbers fell in other categories.

Kai Luey, the Auckland branch chairman of the New Zealand Chinese Association, says family reunions through migration "can be good socially" for immigrant Chinese families.

"Having their parents here provides stability within individual families, allowing them to go out to work knowing their kids are being well cared for at home," Mr Luey said.

"But many of these older Chinese migrants do not integrate well because of language and cultural adaptation, and many end up lonely or having to live within their own enclaves."

Last year, 14,570 approvals - 32 per cent of the total - were through the department's family migration categories. That was a 10 per cent increase on the previous year.