He is taking issue with comments made on Wednesday
Paul Murphy has accused the Taoiseach Leo Varadkar of defaming him.
He is to make an official complaint to the Dáil authorities.
He claims Mr Varadkar accused him of criminal behaviour in the Dáil on Wednesday, and is also complaining about four other Fine Gael TDs.
Deputy Murphy is already facing investigation by the Dáil's disciplinary committee over his own alleged abuse of privilege in exchanges on Wednesday.
But he is now accusing the Taoiseach of defaming him in exactly the same exchange.
Mr Varadkar said Mr Murphy's behaviour in Jobstown was "thuggery" - a claim which he says is defamatory.
He says that by describing the protest as ugly, violent and nasty, he is accusing Mr Murphy of involvement he did not have.
In a letter to be delivered to Leinster House authorities on Friday, he also takes issue with references to water balloons - complaining that Mr Murphy had no connection to this, and that he has therefore been defamed.
Mr Varadkar is not the only subject of the complaint.
The Solidarity TD and his party colleagues also believe Charlie Flanagan, Heather Humphreys, Bernard Durkan, and Mary Mitchell O’Connor are all also in breach of Dáil rules.
Speaking earlier, Deputy Murphy denied abusing his Dáil privilege - and said there is 'legal recourse' open to anyone who thinks they may have been defamed.
He observed: "I had made exactly the same allegation outside of the Dáil, previously, and I'm happy to make it again outside of the Dáil."