Duncan Garner has called out filmmaker Taika Waititi after he said in an interview he's ashamed of his homeland.

The Thor: Ragnarok director, who won New Zealander of the Year 2017, told Marae the country's reputation overseas isn't the reality.

"I'm not very proud of coming from a place that everyone overseas thinks it's this pure, clean, green country but, in reality, all our lakes and waterways are poison.

"We've got a lot to learn about our depression rates, our suicide rates, teen suicide rates, child poverty numbers and the housing crisis."