Green Party of Ontario

Green Party of Ontario
Parti vert de l'Ontario
AbbreviationGPO
PVO
LeaderMike Schreiner
PresidentArd Van Leeuwen
Deputy leadersAislinn Clancy
Matt Richter
Founded1983 (1983)
HeadquartersSuite 232, 67 Mowat Avenue,
Toronto, Ontario, Canada
IdeologyGreen politics
Political positionCentre-left
Colours  Green
Seats in the Legislature
2 / 124
Website
gpo.ca

The Green Party of Ontario (GPO; French: Parti vert de l'Ontario, PVO) is a political party in Ontario, Canada. It has run candidates in every Ontario election since 1985, and has contested every riding in elections since 2007.

The party's support peaked in the 2007 election at 8% of the popular vote, but dropped in the following election in 2011. In the four general elections since, its vote share has hovered around the 5% level. In the 2025 election, Green Party candidates were elected in two ridings.

The party is led by Mike Schreiner, who has represented the riding of Guelph since he first won election there in 2018 and became his party's first member of the Legislative Assembly of Ontario. The party gained a second MPP when Aislinn Clancy won the 2023 Kitchener Centre byelection. She held on to the seat in the 2025 general election.