8 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Defiance | 1 | 17,041 | 17,045 | -0.01% | 1,333 | 12.79 | City |
| Hicksville | 2 | 3,417 | 3,429 | -0.06% | 1,338 | 2.55 | Village |
| Sherwood | 3 | 3,330 | 3,277 | -0.78% | 3,086 | 1.08 | CDP |
| Sherwood | 4 | 816 | 803 | 0.37% | 524 | 1.56 | Village |
| Brunersburg | 5 | 518 | 281 | 7.25% | 1,102 | 0.47 | CDP |
| Ney | 6 | 298 | 303 | -0.33% | 760 | 0.39 | Village |
| Florida | 7 | 210 | 217 | -0.47% | 933 | 0.23 | Village |
| Pulaski | 8 | 110 | 94 | -0.9% | 701 | 0.16 | CDP |
Defiance is the largest city in Defiance County, with a population of 17,041.
Pulaski is the smallest city in Defiance County.
There are 8 cities in Defiance County, Ohio.