Green Party TDs and senators have backed a motion to ask Hazel Chu to step aside from her duties as partyperson while she is campaigning for the Seanad by-election.
It was passed by 11-5 votes at a meeting of the parliamentary party, who will now communicate the decision to the executive committee.
Ms Chu is currently a councillor and Lord Mayor of Dublin.
Green Party leader Eamon Ryan said the candidacy of Ms Chu in the Seanad by-election was not helpful at what is a sensitive time for the coalition.
He said backing the other Government candidates would strengthen the party's ability to implement the promises in the programme for government.
Deputy leader Catherine Martin argued that the motion should not go ahead, as it would be divisive.
However, others argued that it was needed to calm the controversy.
They said it would not have been tabled had Ms Chu "done the right thing" and stepped back from her role as chair of the party while the Seanad campaign is under way.
Some members argued that the motion was necessary to restore confidence in the functioning of the party in Government.
Ms Chu is not bound to step aside temporarily by the parliamentary party's vote tonight.
She can, should she decide, defy the vote and remain as chair.
Under the Green Party constitution, it is only a vote of the party membership that can compel her to stand down.