Sandusky County is a county in the U.S. state of Ohio. As of the 2010 census, the population was 60,944. Its county seat is Fremont. The county was formed on February 12, 1820 from portions of Huron County. It is named for a native word meaning "water" (Wyandot: saundustee).The Fremont, OH Micropolitan Statistical Area includes all of Sandusky County.