A quarter of gay people surveyed in a major EU poll say they have been subjected to attacks or violent threats in the past five years.
The survey found poorer and younger respondents were more likely to face discrimination due to their sexuality.
The poll, carried out by the EU's Fundamental Rights Agency, coincides with International Day against Homophobia and Transphobia.
26% of respondents had been attacked or threatened with violence in the past five years.
66% of LGBT people across all EU member states were scared of holding hands in public with a same-sex partner.
Two out of three respondents hid or disguised being gay at school.
At least 60% personally experienced negative comments or conduct while over 80% in every EU member state recall negative comments or bullying at school.
The survey found that transgender people are the most affected among LGBT respondents, particularly in employment and healthcare.
About 30% said they were victims of violence or threats of violence more than three times in the year before the survey.
"Everyone should feel free to be themselves at home, work, at school and in public – but clearly, LGBT people often don't," said FRA Director Morten Kjaerum.
A spokesman for a group which represents the young LGBT community in Ireland said the survey contained mixed results for Ireland.
Speaking on RTÉ's News at One, Belongto director Michael Baron said that although the survey contained some positives, Ireland was still dealing with a “long legacy” in terms of its treatment of the LGBT community.
While acknowledging that the situation is improving for young LGBT people, he said people between the ages of 18 and 34 are still the least likely to seek help when it comes to instances of homophobia.