Senator Dan Boyle has been elected Green Party chairperson following a postal ballot.
A total of 777 votes were cast, representing 50% of the party's 1552 eligible members.
Votes were counted on a 'preferendum' basis with five points for every first vote, four for second, three for third, two for fourth and one for every fifth vote cast.
There were five candidates for the post, which became vacant on the election of John Gormley as party leader.
The other candidates for the job were Dublin Mid-West TD Paul Gogarty; Dublin City Councillor Bronwen Maher; John Barry, the co-chair of the party's Northern Ireland Regional Council; and long-standing activist Phil Kearney.