Hardinsburg is a town in Posey Township, Washington County, in the U.S. state of Indiana. The population was 248 at the 2010 census.
Hardinsburg was laid out in 1838 by Aaron Hardin, and named for him. Aaron Hardin operated the first store in Hardinsburg and had kept store for several years before the town was started. Hardinsburg was incorporated as a town in 1849.
The Hardinsburg post office has been in operation since 1838.
Hardinsburg is located at 38°27′38″N 86°16′41″W.
According to the 2010 census, Hardinsburg has a total area of 2.03 square miles (5.26 km2), all land.
As of the census of 2010, there were 248 people, 96 households, and 61 families living in the town. The population density was 121.6 inhabitants per square mile (47.0/km2). There were 111 housing units at an average density of 54.4 per square mile (21.0/km2). The racial makeup of the town was 100.0% White. Hispanic or Latino of any race were 0.4% of the population.
There were 96 households, of which 35.4% had children under the age of 18 living with them, 49.0% were married couples living together, 8.3% had a female householder with no husband present, 6.3% had a male householder with no wife present, and 36.5% were non-families.