One Yonge Street is a 25-storey office building in Toronto, Ontario, Canada. The building served as the headquarters of Torstar and its flagship newspaper, the Toronto Star, from 1971 to 2022. It is 100 metres tall and built in the International style. It was built as a replacement to the Old Toronto Star Building, which was located at 80 King Street West. That building was torn down to make room for First Canadian Place.

Torstar Corporation is a Canadian mass media company which primarily publishes news. In addition to the Toronto Star, its flagship and namesake, Torstar also publishes daily newspapers in Hamilton, Peterborough, Niagara Region, and Waterloo Region In addition to the Metroland Media Group and a minority position on Canadian Press. The corporation was initially established in 1958 to take over operations of the Star from the Atkinson Foundation after a provincial law banned charitable organizations from owning for-profit entities. From 1958 to 2020, the class A shares of Torstar were held by the families of the original Atkinson Foundation trustees. The private investment firm NordStar Capital LP, now owned by Jordan Bitove, acquired the company in 2020.