This year included a separate survey of infrastructure covering electricity, water, phone and mail services, public transport, traffic congestion and the range of international flights available.
Auckland's 43rd place on that survey was below the five Australian state capitals but ahead of many other cities which scored highly on quality of life such as Geneva and San Francisco.
"Surveyors commented on the efficiency of public transport for a city of Auckland's size," Mercer said.
But the city ranked worst-equal with Melbourne among the Australasian cities for traffic congestion.
Auckland Mayor Len Brown said the city's transport infrastructure lowered its ranking.
"We are working hard to give Auckland a fully integrated transport system, and steps like rail electrification and next year's arrival of the first of our new electric trains, protecting and designating the route for the City Rail Link, and our integrated ticketing system roll-out will make a significant positive impact."
The quality of life survey scored cities on their political stability, crime, banking and foreign exchange services, personal freedom, medical services, international schools, infrastructure, restaurants and other leisure facilities, availability of consumer goods, rental housing and climate.
All Australasian cities except Christchurch rated perfect scores for housing because of their "attractive rental properties and prestigious residential districts".
Auckland and Wellington also received perfect scores for banking and foreign exchange services.
Auckland rated ahead of all other Australasian cities for medical services and health, which includes air pollution, sewage, waste disposal and infectious diseases.
It was also given near-perfect scores for availability of consumer goods and personal freedom, and scored well on leisure facilities.
Sydney received the highest score in Australasia for education because of its "variety and reputation of available schools, whether German, French, Japanese or English-speaking".
Although the Mercer survey is designed for multinational executives, surveys of ordinary people have also found relatively high quality of life in New Zealand.
A study by Wellington research group Motu found the country ranked ninth out of 24 developed countries on the New Economics Foundation's "happy planet index" of life satisfaction, just ahead of Australia, even though NZ income per person was only 22nd out of the 24.
