Ontario Liberal Premier Kathleen Wynne made the announcement on Tuesday, as part of an overhaul of the province's labour laws.
The minimum wage would be raised in two steps, from C$11.40 to C$14 on 1 January 2018, and then to C$15 a year later.
Alberta also plants to raise its wage to C$15 in October 2018.
That would give Ontario the highest wage in the country for most of 2018.
Wynne billed the raise as "the largest increase in our province's history."
"People are anxious about their jobs, and they're anxious about the future," she said during a press conference on Tuesday. "In a time of change like this, when the very nature of work is being transformed, we need to make certain that our workers are treated fairly."
The minimum wage will be tied to inflation once it reaches C$15 in 2019.
The reforms also include changes to paid vacations, emergency leave and makes it easier for people to join a union.
Ms Wynne's government has been sliding in the polls and faces an election challenge in June 2018. In recent months, she has introduced a minimum income pilot project, free medication for people under 30 and expanded rent controls, both moves popular with large portions of the population.
But not everyone is in favour of the changes.
The Ontario Chamber of Commerce said it is concerned about the impact the wage hike will have on businesses and the economy.
"Many businesses will not be able to find a way to absorb these costs and many ... will have to go out of business," said Karl Baldauf, vice president of policy and government relations at the Ontario Chamber of Commerce.
Canada's largest province is raising the minimum wage to C$15 ($11.14, Â£8.66) an hour.