Sixty gay and bisexual men were diagnosed with HIV in the first six months of the year.
The latest figures, launched today which is World Aids Day, show that gay men continue to be the most likely group to acquire the infection in Ireland.
Tiernan Brady, of the Gay and Lesbian Equality Network, said HIV remains an issue of critical concern for gay and bisexual men.
"A focus on targeted prevention and awareness-raising of HIV with this group of men is critical," he said.
"This focus, coupled with efforts to promote testing for HIV and other sexually transmitted infections amongst gay and bisexual men can lead to a reduction in HIV infection rates."
Data from the HSE's Health Protection Surveillance Centre (HPSC) for the first half of the year revealed there were 152 new HIV diagnoses.
Almost 40 per cent (60 people) were men who have sex with other men and 36.6 per cent of those were aged between 15 and 29 years.
The HSE and the Gay Health Network, in association with Dublin City Council, have launched a National HIV Prevention and Sexual Health Awareness Programme.
Key messages will include promotion of issues of HIV prevention, testing, condom use, and HIV-related stigma; increasing access to condoms via the Man2Man.ie website; and health promotion workshops for MSM.
The programme was published today by Minister of State for Primary Care Róisín Shortall.
Ms Shortall said many aspects of the HIV prevention agenda had proven successful in the past but that recent statistics showed that "more and more people are either not hearing or are choosing to disregard the messages and are engaging in risky behaviours".
"It is essential we identify the reasons for this and deliver targeted prevention programmes in order to address this situation," she said.
Mr Brady said HIV has become a growing risk for a new generation of young gay and bisexual men. "For the first six months of this year, young men under 30 accounted for 37 per cent of all cases," he said.
"This shows the importance of the upcoming HIV prevention campaign by the Gay Health Network targeting young gay and bisexual men."
PA