Rainy River District is a district and census division in Northwestern Ontario in the Canadian province of Ontario.

It is the only division in Ontario that lies completely in the Central Time Zone, except for the township of Atikokan (including Sapawe and Kawene to the east) observing Eastern Standard Time for part of the year.

It is known for its fishing and its location on the US border opposite International Falls, Minnesota, and Baudette, Minnesota.

Municipalities Unorganized area: Reserves: As a census division in the 2021 Census of Population conducted by Statistics Canada, the Rainy River District had a population of 19,437 living in 8,315 of its 10,679 total private dwellings, a change of −3.3% from its 2016 population of 20,110.

[1] As of 2013, the Rainy River District School Board has partnered with the Seven Generations Education Institute, the Ministry of Education, and local First Nations communities in development of new technologies and programs for revitalization of the Ojibwe language.