Mr Hart's net worth was calculated at $US4.7 billion ($NZ8.1 billion), well clear of Mr Packer who reclaimed the title of richest Australian with a net worth of $US3.1b, the magazine reported in its May issue.
It was first time since Forbes Asia began keeping track of global fortunes that a New Zealander had emerged on top in Australasia.
According to the magazine, which described him as "the master of the leveraged buyout", Mr Hart's net wealth dropped $US700 million in the past year, while Mr Packer's dropped by $US2.2b.
Mr Hart was well clear on Forbes Asia's New Zealand rich list, with Dubai-based brothers Christopher and Richard Chandler equal second with net worth of $US1b apiece.
Lynette Erceg, the widow of Independent Liquor founder Michael Erceg, was next on $US630m while Moscow-based Stephen Jennings (co-founder of brokerage and bank Renaissance Capital), rounded out the New Zealand top-five on $US500m.
On the Australian rich list, Mr Packer topped Westfield Group founder Frank Lowy ($US2.8b) and property magnate Harry Triguboff ($US2b).
