Campaigners have called on the Government to hold Facebook accountable for its "harmful practices" in promoting damaging material to young people.
A number of members of campaign group Uplift Ireland travelled from Cork to protest outside the offices of Facebook in Dublin and Leinster House.
The group is calling on the Government to introduce tougher legislation to tackle social media giants.
The protest is in response to recent allegations that the tech giant is failing to protect young people and prevent extremism.
The protesters were dressed in full face masks depicting Instagram filters which alter the shape of the face.
One demonstrator was in a cage wearing a bodysuit which alters the shape of the body and a filter mask, while another held a placard with the message "Face up to Facebook, Minister Catherine Martin".
Layla Wade, campaigner with Uplift, said: "We are here today to support some of our youngest members and we are calling on Minister Catherine Martin, Minister of State Robert Troy and all of the TDs in Dail Eireann to face up to Facebook.
"What we mean by that is we want them to hold them accountable for the harmful practices that their business model, their platform Instagram is inflicting on young people.
"The proof is in the pudding and we have known anecdotally about the harmful effects of social media on younger people, and people are coming to the fore to speak about that.
"Facebook is profiting from this harm. They made nine billion dollars (7.8 billion euros) in the last quarter alone and we are here to tell the Government they have a responsibility to step up and hold them accountable."
A number of TDs and Senators also supported the protest, including Social Democrat TD Holly Cairns, Fine Gael senator Emer Higgins and Sinn Fein senator Fintan Warfield.
