The company said Monday that the staff reductions are part of the London-based company's efforts announced last February to streamline global operations to reduce costs.
"We are in a cyclical industry and we have to adapt with the market," spokeswoman Claudine Gagnon said.
The reduction of corporate jobs that support various metal groups will begin in a few weeks and be completed by year-end.
About 800 employees currently work for the aluminum and other metal group divisions in Montreal.
The aluminum division's global headquarters will remain in the city but the name Alcan will gradually become less prominent. Rio Tinto will the identity of the featured tenant in the new, 26-storey Deloitte tower that will open next to the Bell Centre — home of the Montreal Canadiens.
Rio Tinto will occupy the top floors of the tower beginning in the first quarter of 2016.
The Rio Tinto Alcan moniker will still be used for Montreal's new planetarium and sponsorship events like the Montreal Jazz Festival.
Alcan has been in use since 1925 for the company, formerly the Aluminum Company of Canada. It was acquired by Rio Tinto in 2007 for US$38.1 billion.
In addition to aluminum operations in Quebec and British Columbia, Rio Tinto owns a majority stake in the Iron Ore Company of Canada and the Diavik diamond mine in the Northwest Territories.
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