Jack MacLaren (born c. 1951) is a Canadian former politician who represented the eastern Ontario riding of Carleton—Mississippi Mills in the Legislative Assembly of Ontario from 2011 to 2018. Originally elected as a member of the Progressive Conservative Party of Ontario, he was removed from the party's legislative caucus in 2017 by party leader Patrick Brown after a video recording surfaced of him suggesting that the party would repeal Franco-Ontarian language rights in the province. MacLaren announced later that day that he had joined the Trillium Party of Ontario, becoming that party's first MPP.