Senator Dan Boyle has been elected chairman of the Green Party by the party membership.
The party confirmed the result of the ballot this evening.
A total of 777 votes were cast, representing 50 per cent of the party's 1,552 eligible members.
Five candidates contested for the position, which involves chairing meetings of the national convention, management committee and other meetings related to electoral and party strategy.
Under the voting system in operation, Mr Boyle gained the most 'points', followed by TD Paul Gogarty, Cllr Bronwen Maher, John Barry and Phil Kearney.
Mr Boyle thanked the members of the party for placing their confidence in him.
"The process of meeting with, listening to and discussing where the Green Party now stands as a party of government, has been immensely rewarding," he said in a statement.
"Each of the five candidates for this post have and will offer the party huge scope for our future. As chair I intend to ask each of the candidates in helping us reach that potential. Having shown we can make decisions and take responsibilty, the potential for the Green Party in Irish politics is great."