Human immunodeficiency virus can lead to Aids, or acquired immune deficiency syndrome.
Last year, of the 217 new diagnoses in NZ, 136 were amongst the gay, bisexual and other men who have sex with men, of which 86 were infected in NZ.
The ministry spokesman said the Singapore ban was lifted "given the current context with more than 5000 Singapore residents living with HIV and the availability of effective treatment".
The Straits Times reported that foreigners here, excluding permanent residents or spouses of Singaporeans, would be deported and put on a permanent blacklist if found to be HIV positive.
"Lifting the short-term travel restrictions...poses very low additional risk of HIV transmission to the local population," the ministry spokesman added.
"However public health risk posed by long-stayers is not insignificant, hence the restriction on long-term visits has been retained."
The NZ Aids Foundation said on its website that New Zealand did not have specific policies on HIV as it is part of Immigration New Zealand's overall health policy.
"People with HIV can apply for a visa (to enter NZ), but that doesn't guarantee they will be approved," the foundation said.
- Lincoln Tan travelled to Singapore with the help of the Asia New Zealand Foundation