Legionnaires' disease has been linked to another death in Auckland.
The latest death, which occurred several weeks ago, was the second of the current outbreak, which began in late February.
The person was already very unwell, the Auckland Regional Public Health Service says.
The death of an elderly woman with Legionnaires, who was also already unwell, was confirmed in early April.
There have been 16 confirmed cases of the bacterial infection, but only one case in the last 28 days.
Legionnaires is a form of pneumonia and can be life-threatening to vulnerable people.
About one in 20 cases of Legionnaires' disease in New Zealand is fatal.
There are normally just one or two cases in the Auckland region in a six-week period.
Officials haven't been able to pinpoint the source of the outbreak, but a region-wide campaign was launched to chemically treat more than 300 Auckland building systems which could harbour Legionella bacteria.
These are buildings which have cooling towers or use an industrial process that recirculates water and generates aerosols.
In 2005, an unmonitored cooling tower in Christchurch was identified as the most likely source of a Legionnaires outbreak which was linked to three deaths.
The disease can be contracted by breathing in mist from water or dust from bagged potting mix or compost that contains the bacteria.
It is not passed from person to person.