Wannaska is an unincorporated community in Roseau County, Minnesota, United States.
The community is located 13 miles south of Roseau on State Highway 89 (MN 89). Wannaska is located within Grimstad Township and Mickinock Township. Wannaska has a post office with ZIP code 56761.
Nearby places include Roseau and Hayes Lake State Park. The South Fork of the Roseau River flows through the community.