A 23-year-old New Zealander who begged Australia's immigration minister not to deport him back to this country has died in Australia's Supermax prison.

The Sydney Morning Herald reports that Junior Togatuki committed suicide after writing farewell messages to his family.

His Australian visa had been revoked, and as his release date passed, his isolation cell at the Goulburn prison became a defacto immigration detention centre.

Mr Togatuki had told Immigration Minister Peter Dutton he would be "lost" once he was deported to New Zealand because he would have no family or friends, no home, and no job.

The New Zealander, who was aged four when he moved from Auckland to Sydney, said he had "no memory" of New Zealand and was "uncomfortable having the identity of a kiwi".

The New Zealand Government understands about 200 New Zealanders are being held in seven Australian detention centres.