A small blaze broke out at Wiri Women's Corrections Facility in South Auckland overnight.
Fire and Emergency New Zealand crews put out the fire, which started about 9.30pm.
Northern communications shift manager Colin Underdown said no one was believed to have been injured in the blaze.
The fire wasn't the first at the prison - emergency services were called to two small fires last Monday.
It was revealed the fires were set by two lovelorn prisoners who wanted to share a cell.
Regional Commissioner Jeanette Burns called the blaze an example of "poor behaviour", which had put other prisoners and staff at risk.
"Two prisoners who were in an intimate relationship, and who wanted to be placed in a unit together, have been at the centre of the unrest and had made it clear they would create as much disruption as possible until they got their way.
"The prisoners are currently in separate units and are settled and compliant."
Three prisoners were taken away for medical assessment for suspected smoke inhalation.
Heightened tension at the prison also saw Corrections officers yesterday transferring a transgender prisoner from the women's prison back to a men's prison.
The prisoner had identified as female and been approved to be placed in a women's prison since 2016.
Burns said: "The prisoner had been smashing windows and inciting other prisoners to be violent as they wanted to be returned to a men's prison."
The return to the men's prison was the first of its kind since Corrections' transgender prisoner policy started in 2014.