According to Cambodia Police, 46-year-old Jann Nicholas Hazlett, known as Nick, died of a heart attack on May 18.
He was found in a hotel room at the Khavi Villa, in Phnom Penh.
Local authorities stated that Hazlett's body was transported to the Khmer-Soviet Friendship Hospital.
Images of Hazlett's passport, shown in foreign media reports, show he was a New Zealand citizen, from Invercargill.
New Zealand's Ministry of Foreign Affairs and Trade said it is providing consular assistance to the family of a New Zealander in Cambodia.
For privacy reasons no further information will be provided, it said.
Hazlett was the director of Symmetry Asia, which provides recruitment solutions across Southeast Asia, Hong Kong and Australia.
His online company profile says he had worked in a number of countries since leaving New Zealand in 1996. Hazlett, and his wife and child, have been based in Singapore since early 2011.
The New Zealand Herald has made attempts to contact Hazlett's family.
