Elizabeth Dowdeswell, a former undersecretary general of the United Nations with a long public service record, will be sworn in Sept. 23, during a ceremony in the province's legislative chamber.
Her appointment was announced last month by Prime Minister Stephen Harper, who praised her "wealth of expertise" and her work promoting sustainable development in Ontario and across the country.
Dowdeswell is currently CEO of the Council of Canadian Academies and previously lived in Saskatchewan, where she was a teacher.
Both Premier Kathleen Wynne and current Lt.-Gov. David Onley say they look forward to welcoming Dowdeswell to her new role.
Onley, who has been lieutenant-governor for seven years, will remain in the post until Dowdeswell's installation.