The Ministry of Health and Te Whatu Ora confirmed a person who had recently returned from overseas was currently isolating in the South Island following a positive test result.
As with the previous three cases of monkeypox in New Zealand, MoH regarded the risk of community transmission as low.
"Significantly, there is no evidence of community transmission from this case and public health staff has assessed the risk of transmission from this case as low," said the ministry.
To protect the privacy of the person and their contacts, the ministry said it would not be making further comment on this case, at this stage.
The ministry said it had provided advice to public health units, primary health organisations and sexual health clinics to assist with identifying potential cases.
"Health professionals are being reminded to remain vigilant for any possible cases of monkeypox."
A third case of monkeypox was confirmed earlier this month after a person returned from international travel.
That person was also isolating in the South Island.
Two previous cases had been reported in New Zealand in July. By the end of the month, health officials reported they had since recovered.
Ministry public health advice for those with monkeypox is to isolate at home until the scabs from lesions have fallen off.
Monkeypox virus is part of the same family of viruses as variola virus, which causes smallpox.
Monkeypox symptoms are similar to smallpox symptoms, but milder, and monkeypox is rarely fatal. Monkeypox is not related to chickenpox.
