The gender pay gap is a human rights issue and action needs to be taken, the Human Rights Commission says.
The gap between what men and women are paid has gone up from 9.9 percent last year to 11.8 percent.
The commission says New Zealand cannot continue with business as usual.
"The fastest way to reduce our entrenched gender pay gap is to improve the wages of those New Zealanders in the lowest paid jobs - the overwhelming majority of whom are women," equal employment commissioner Dr Jackie Blue says.
In 2014, two-thirds of minimum wage earners were women.
Gender equality was a human rights issue, she said.
"Gender equality doesn't just improve the lives of women it improves the future of entire generations."
Minister for Women Louise Upston says the increase is disappointing after a 17-year downward trend.
Workers, employers, career advisers and business leaders need to take action, she said.
Women should be encouraged into fields where they have been traditionally under-represented, such as technology, construction and trades which were growth and high wages, Ms Upston said.
The Greens, the Pay Equity Coalition and the Public Service Association all say the government has been sitting on its hands.
"Women are literally paying the price for National's do-nothing approach to the gender pay gap," Greens' Jan Logie says.
The PSA says it's shameful that 40 years after the Equal Pay Act became law, women are still not paid fairly.