Ardern said at the time that she was "flattered" to be included on the list, which was released a week after she became Prime Minister.
"I definitely don't think it's going to change the expectation that I still unload the dishwasher at home," she said at the time.
"It does reflect there is a need for us to have more women in politics and positions of influence and power globally. I'm certainly flattered at being included in the list, but I'd like to see a lot more women in contention."
In releasing this year's list of 100 most powerful women, Forbes said: "At no time has more light been shone on women leaders and the need for more diversity. From #MeToo to #TimesUp to 'We Too', a term most recently used to describe the rise of women's voices in the United Nations this year, women are mobilising for change.
"The women on Forbes 15th annual Most Powerful Women list are among the toughest, smartest leaders the world has today. They are creating solutions for some of the world's biggest problems and making their mark."
The top 10
1: Angela Merkel, Politics
2: Theresa May, Politics
3: Christine Lagarde, Economy
4: Mary Barra, Automotive
5: Abigail Johnson, Finance and Investments
6: Melinda Gates, Philanthropy/NGO
7: Susan Wojcicki, Technology
8: Ana Patricia Botín, Finance and Investments
9: Marillyn Hewson, Manufacturing
10: Ginni Rometty, Enterprise Technology