Mio (/ˈmaɪoʊ/ MY-oh) is an unincorporated community and census-designated place (CDP) in Oscoda County in the U.S. state of Michigan. It is the county seat of Oscoda County. The population of the CDP was 1,690 at the 2020 census. Mio is situated along the boundary between Mentor Township on the east, Big Creek Township on the west, and Elmer Township to the northwest. As an unincorporated community, Mio has no legal autonomy as an incorporated municipality.