| Official Name: | Lydia, South Carolina |
| Settlement Type: | Census-designated place |
| Mapsize: | 250px |
| Pushpin Map: | South Carolina |
| Pushpin Label: | Lydia |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | South Carolina |
| Subdivision Type2: | County |
| Subdivision Name2: | Darlington |
| Unit Pref: | Imperial |
| Area Footnotes: | [1] |
| Area Total Sq Mi: | 2.64 |
| Area Land Sq Mi: | 2.64 |
| Area Water Sq Mi: | 0.00 |
| Population As Of: | 2020 |
| Population Footnotes: | [2] |
| Population Total: | 572 |
| Population Density Sq Mi: | 216.42 |
| Timezone: | Eastern (EST) |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Ft: | 213 |
| Coordinates: | 34.2878°N -80.1203°W |
| Postal Code Type: | ZIP code |
| Postal Code: | 29079 |
| Blank Name: | FIPS code |
| Blank Info: | 45-43135 |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 2629835[3] |
| Area Total Km2: | 6.85 |
| Area Land Km2: | 6.85 |
| Area Water Km2: | 0.00 |
| Population Density Km2: | 83.56 |
right|thumb|Lydia Plantation houseLydia (formerly Mount Elon) is an unincorporated community and census-designated place (CDP) in Darlington County, South Carolina, United States. As of the 2010 census, the population of the CDP was 642.[4] It is the location of Lydia Plantation, which is listed on the U.S. National Register of Historic Places.
Lydia is in western Darlington County, just east of the Lee County line. U.S. Route 15 passes through the community, leading northeast 7miles to Hartsville and southwest 10miles to Bishopville. South Carolina Highway 34 leads east to Darlington, the county seat.
According to the U.S. Census Bureau, the Lydia CDP has an area of 6.8sqkm, all land.[4]