Elkton is a city in Giles County, Tennessee, United States. The population was 578 at the 2010 census. Elkton is located in southeastern Giles County. Most of the city is on the north bank of the Elk River, a southwest-flowing tributary of the Tennessee River. According to the United States Census Bureau, Elkton has a total area of 2.2 square miles (5.6 km2), all land. As of the census of 2000, there were 510 people, 203 households, and 142 families residing in the city. The population density was 340.6 people per square mile (131.3/km2). There were 226 housing units at an average density of 150.9 per square mile (58.2/km2).