Vermilion is a city in Erie and Lorain counties in the U.S. state of Ohio, on Lake Erie. The population was 10,594 at the 2010 census. The current mayor is Eileen Bulan. The Lorain County portion of Vermilion is part of the Cleveland–Elyria–Mentor Metropolitan Statistical Area, while the Erie County portion is part of the Sandusky Metropolitan Statistical Area.