East Main Street–Douglass Heights Historic District is a national historic district located at Union, Union County, South Carolina.

The district encompasses 55 contributing buildings in a primarily residential section of Union.

The houses were built between about 1823 to 1940, and are in a variety of popular architectural styles include Neo-Classical, Queen Anne, and Colonial Revival.

Located in the district is the separately listed Union High School-Main Street Grammar School.

This article about a property in Union County, South Carolina on the National Register of Historic Places is a stub.