In order of quality of experience, the top six countries were Sweden, Norway, Germany, the Netherlands, Canada and Switzerland.
Australia was 14th, behind Ireland in 12th and Britain 13th.
That New Zealand did well in the international comparison was no surprise to Associate Professor Susan St John, co-director of the New Zealand Retirement Policy and Research Centre.
"The broad coverage of the state pension is very important," she said. "The flat rate amount is modest but for most most, reasonably adequate and overall hardship rates are very low."
New Zealand did not have the poverty among older women seen in some other developed countries, so she was surprised the index put it 43rd for income security, "which seems far too low".
"It does not seem plausible that Mauritius can beat us at seventh even though it, too, has a universal pension. It seems to reflect the particular way they have counted things, and this aspect of the index is likely to be revised over time."
Grey Power national president Roy Reid said he was not surprised that New Zealand fared better than Australia.
"From a superannuation point of view it should. I have family in Australia and I believe we are better off in New Zealand."
However, Mr Reid said that because New Zealand had a small population, he would expect its ranking to improve.
Senior Citizens Minister Jo Goodhew said seventh sounded okay, but she was looking for ways to improve the lives of older New Zealanders.
Yesterday was the International Day of the Older Person and she launched the document Healthy, Independent, Connected and Respected.