The Union of Students in Ireland is urging anyone with information in relation to the alleged sharing of inappropriate postings on social media between students attending University College Dublin to contact college authorities.
UCD has written to 27,000 students about the investigation, warning them of possible expulsion.
In the email, the college's deputy president Mark Rodgers, said its investigation would determine if there was any illegal activity and this would be referred to the relevant authorities.
Last week, university newspaper The College Tribune alleged that up to 200 male students were members of a private Facebook group used to share stories and rate photos of women.
Speaking on RTÉ's Morning Ireland, USI President Kevin Donoghue urged anyone who thinks they may be a victim of the allegations to contact the student union where they would be directed to appropriate supports.
Mr Donoghue said he does not believe that these allegations are indicative of what could be happening in other third-level institutes, but urged anyone with any concerns to come forward.
"It is absolutely crucial that you report it to the college authorities where that is appropriate and to An Garda Síochána as well if you are aware of any of these instances.
"You can go to your students union; they will provide you with the support that you need in terms of where you need to go.
"If you are aware of any of this kind of behaviour going on, it is absolutely crucial that you report it because it is completely unacceptable in this day and age that this kind of stuff would be carried out by students in any college" he said.
Response to allegations of student Facebook group chat rating “girls they have slept with” pic.twitter.com/pL6oCeA5mv
— UCD: Uni College Dub (@ucddublin) February 5, 2016
