Hymera is a town in and the principal center of Jackson Township, Sullivan County, Indiana, United States. The population was 801 at the 2010 census. It is part of the Terre Haute Metropolitan Statistical Area.
According to the United States Census Bureau, the town has a total area of 0.7 square miles (1.8 km²), all of it land.
As of the census of 2000, there were 833 people, 331 households, and 228 families residing in the town. The population density was 1,184.5 people per square mile (459.5/km²). There were 389 housing units at an average density of 553.1 per square mile (214.6/km²). The racial makeup of the town was 99.40% White, 0.24% Native American, and 0.36% from two or more races.