11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Beaver Dam | 1 | 3,535 | 3,536 | 0% | 1,164 | 3 | City |
| Beaver Dam | 2 | 3,535 | 3,534 | 0% | 1,164 | 3 | City |
| Hartford | 3 | 2,649 | 2,666 | -0.11% | 934 | 3 | City |
| Hartford | 4 | 2,649 | 2,664 | -0.11% | 934 | 3 | City |
| Fordsville | 5 | 452 | 443 | 0.44% | 1,009 | 0 | City |
| Fordsville | 6 | 452 | 442 | 0.44% | 1,009 | 0 | City |
| Centertown | 7 | 418 | 418 | 0% | 1,335 | 0 | City |
| Centertown | 8 | 418 | 417 | 0% | 1,335 | 0 | City |
| Rockport | 9 | 265 | 264 | 0% | 381 | 1 | City |
| Rockport | 10 | 265 | 264 | 0% | 381 | 1 | City |
| Rosine | 11 | 128 | 106 | 0.79% | 266 | 0 | CDP |
Beaver Dam is the largest city in Ohio County, with a population of 3,535.
Rosine is the smallest city in Ohio County, with a population of 128.
There are 11 cities in Ohio County, Kentucky.