Pauline O'Reilly (born 1974/1975) is an Irish Green Party politician who served as a Senator for the Labour Panel from June 2020 to January 2025,[2][3] and chair of the Green Party since December 2021.

[4] O'Reilly stood unsuccessfully in Galway West at the 2020 general election.

[9] On 24 March 2021, O'Reilly was one of three Green Party senators to table a motion of no confidence against party chair Hazel Chu, after Chu announced her candidacy in a Seanad by-election as an independent, with O'Reilly stating she does not believe it's appropriate "to run as an independent candidate and also to be a chair of a party that’s in government and is supporting government candidates".

[10] On 16 December 2021, O'Reilly was elected as Chair of the Irish Green Party, succeeding Chu.

[12] O'Reilly was the Green Party's candidate for the Midlands–North-West constituency at the 2024 European Parliament election.