3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Harrodsburg | 1 | 9,319 | 9,069 | 0.54% | 1,346 | 6.92 | City |
| Burgin | 2 | 1,011 | 983 | 0.6% | 805 | 1.26 | City |
| Salvisa | 3 | 218 | 167 | -5.63% | 118 | 1.84 | CDP |
Harrodsburg is the largest city in Mercer County, with a population of 9,319.
Salvisa is the smallest city in Mercer County.
There are 3 cities in Mercer County, Kentucky.