New Zealand has held its place as one of the top five most peaceful countries, according to an annual study.

The Global Peace Index has kept New Zealand in fourth spot, for the third straight year.

Iceland tops the list, followed by Denmark and Austria.

The index uses 23 indicators to measure peace - including political instability, UN peacekeeper funding and the number of security officers and police.

GPI's international expert panel chair Professor Kevin Clements said it's a matter of maintaining our peacefulness on a global stage.

"I think it just indicates that New Zealand has been fairly constant on both internal and external indicators of peace."

Panama made the biggest leap up the index, rising 24 places to 49th, while Yemen dropped nine places to 158th.

Portugal rose nine places to fifth, while Australia is in 15th.

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