Kewaunee County is a county located in the U.S. state of Wisconsin. As of the 2020 census, the population was 20,563. Its county seat is Kewaunee. The county was created in 1852 and organized in 1859. Its Menominee name is Kewāneh, an archaic name for a species of duck. Kewaunee County is part of the Green Bay, WI Metropolitan Statistical Area as well as the Green Bay-Shawano, WI Combined Statistical Area.