An organiser of the Pacific International Documentary Film Festival in French Polynesia says while all the entries were good, 'There Once Was An Island' was the clear winner.
The New Zealand film took the top prize from 17 other documentaries.
It's about three people on Takuu atoll in Papua New Guinea's Bougainville province having to deal with the effects of climate change.
Organiser and spokesperson, Eliane Koller, says the film was different.
"What stood out in this movie was that it was really a film fighting for a dying little island and making clear that we have to do something. By showing one little island, reminding us of the general situation in the Pacific and even in the world."
Special prizes were awarded to a Hawaiian film Nono Newa, the Australian film Bastardy and a documentary on New Zealand musicians the Topp Twins.
The public's prize has gone to a French Polynesian documentary called Homeland, the Return to Rurutu.