May announced in Montreal that Jose Nunez-Melo will run under the Green banner in the new suburban Montreal riding of Vimy.
Nunez-Melo was elected to the House of Commons in 2011 as part of the orange wave that swept Quebec.
"I am over the moon to welcome Jose Nunez-Melo who has served in Parliament, as I have since 2011,'' May said.
"We weren't in the same party but we had the same spirit.''
Montreal's La Presse reported this month that Nunez-Melo became embroiled in a dispute with the party over the nomination in the new riding, and quoted him as saying he was blocked from running by party brass.
Nunez-Melo, who came to Canada in 1990 from the Dominican Republic, is one of only a handful of Hispanic Canadians who have sat in the House of Commons.
May says the Greens now have three members who were MPs in the last Parliament, one more than the Bloc Quebecois at dissolution, and is pushing for inclusion in all debates.
Also on HuffPost