Wednesday June 15 is Irish Aids Day.
HSE public STI screening services are almost exclusively based in hospitals and special community clinic settings around Ireland and are free.
The Men who have Sex with Men Internet Survey, launched by the HSE and the Gay Health Network, said that 40% of gay men have never been tested for HIV or other STIs.
It also shows that 21% of those who tested positive for STIs over the past year were new cases; 8% reported that they were HIV positive.
The HSE said there were 244 diagnoses of HIV among gay men last year, compared with 184 in 2014, which is an increase of one third.
Minister of State for Health Promotion Marcella Corcoran-Kennedy said the figures showed a worrying trend.
"We want to ensure people are informed about the risks that are out there, and about what they can do to take responsibility of their own sexual health," she said.
In Chambers nightclub, Cork, Be Sexy Stay Healthy will be providing free rapid HIV testing from 6pm until 8pm.
For more information on sexual health click HERE.