Half of young adults aged between 18 and 24 experienced sexual harassment in the last 12 months, compared with 7% of those aged 65 and older, according to figures from the Central Statistics Office.
Latest data also shows that 20% of adults experienced sexual harassment in the last 12 months.
Women were over twice as likely (28%) to experience sexual harassment than men (13%) and were almost four times more likely to have experienced inappropriate physical contact (15%) than men (4%).
The figures are the latest findings of an extensive survey conducted by the CSO on sexual violence in Ireland.
The results provide detailed analysis specifically around the related topic of sexual harassment in Ireland.
Over one in 12 young adults (8%) reported they had experienced their sexual images or videos being shared without their permission in the last 12 months, compared with 1% of those aged 55-64.
Almost nine in ten adults (87%) who experienced sexual harassment reported that the perpetrator was male.
Half (50%) of men who experienced sexual harassment in the last 12 months did not disclose their experience.
In the last 12 months, 3% of adults experienced stalking with fear of sexual violence.
Most people (70%) who experienced stalking with fear of sexual violence in the previous 12 months disclosed to someone about the experience.
Sexual harassment is defined in the CSO survey as unwanted behaviours that a person may have experienced in the last 12 months, which made the person feel offended, humiliated, or intimidated.
Nationally, the most prevalent sexual harassment experience was where remarks of a sexual nature were made while not online - for example, in person, by text, or phone call.
This included crude or sexually explicit remarks that the person found offensive, humiliating, or intimidating.
Overall, 12% of adults experienced this in the last 12 months, compared with 2% who experienced sexual images or videos of them being shared without their permission.
The most prevalent location for sexual harassment was in a pub, club, or disco, with 18% of men and 29% of women reporting this as a location of an experience.
Overall, more than half of adults (52%) who experienced sexual harassment in the previous 12 months disclosed to someone, and they were most likely to tell a friend (67%).
Stalking is defined in the survey as "persistent unwanted actions such as following you, waiting for you, contacting you by phone, text and/or social media, that are against your wishes or imply threats".
Stalking in the CSO survey was specific to the topic of sexual violence.
In common with the previous publications on sexual violence experiences, women reported having experienced stalking with fear of sexual violence (4%) at a higher level than men (1%) in the last 12 months.
The majority (96%) of those who experienced stalking with fear of sexual violence reported that it was one person, and this was most likely to be a male.
The survey found that most people tell someone about their experience.
Seven in ten (70%) adults who experienced stalking with fear of sexual violence in the previous 12 months disclosed to someone about the experience.
Three-quarters of adults were more likely to tell a friend.
Speaking on RTÉ's News at One, Clíona Saidléar, Executive Director of Rape Crisis Network Ireland, said it is significant that the State has decided to count and define sexual harassment in this manner.
"Specifically, today is about sexual harassment, and one might say that that is the area that is most prone to dismissal, denial, silencing this is really the area where we essentially set up our society to facilitate sexual violence," she said.
"We set up silence, we tell perpetrators what they can get away with in and around the areas of sexual harassment, so it is so important that we have a focus on sexual harassment here, and as we can see the figures are really high."
Ms Saidléar added that this is about "inequality" and "access to public spaces".
