20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Dayton | 1 | 134,189 | 137,496 | -0.49% | 2,404 | 55.81 | City |
| Beavercreek township | 2 | 57,452 | 56,095 | 0.56% | 1,176 | 48.84 | Township |
| Beavercreek | 3 | 47,582 | 46,609 | 0.41% | 1,789 | 26.59 | City |
| Fairborn | 4 | 34,827 | 34,581 | 0.14% | 2,390 | 14.57 | City |
| Xenia | 5 | 25,913 | 25,442 | 0.36% | 1,984 | 13.06 | City |
| Bellbrook | 6 | 7,467 | 7,321 | 0.39% | 2,382 | 3.13 | City |
| Xenia township | 7 | 6,683 | 6,753 | -0.28% | 153 | 43.81 | Township |
| Cedarville township | 8 | 5,939 | 5,887 | 0.29% | 152 | 39.17 | Township |
| Miami township | 9 | 4,970 | 4,941 | 0.02% | 180 | 27.54 | Township |
| Cedarville | 10 | 4,247 | 4,254 | -0.02% | 3,244 | 1.31 | Village |
| Silvercreek township | 11 | 3,810 | 3,732 | 0.47% | 145 | 26.31 | Township |
| Yellow Springs | 12 | 3,727 | 3,704 | 0.13% | 1,354 | 2.75 | Village |
| New Jasper township | 13 | 2,686 | 2,633 | 0.45% | 125 | 21.42 | Township |
| Spring Valley township | 14 | 2,542 | 2,481 | 0.55% | 74 | 34.19 | Township |
| Wilberforce | 15 | 2,170 | 2,418 | -0.28% | 704 | 3.08 | CDP |
| Jamestown | 16 | 2,088 | 2,050 | 0.38% | 1,792 | 1.17 | Village |
| Caesarscreek township | 17 | 1,203 | 1,176 | 0.59% | 44 | 27.43 | Township |
| Spring Valley | 18 | 421 | 415 | 0.24% | 1,583 | 0.27 | Village |
| Bowersville | 19 | 264 | 269 | -0.38% | 1,600 | 0.17 | Village |
| Clifton | 20 | 137 | 134 | 0.74% | 811 | 0.17 | Village |
Dayton is the largest city in Greene County, with a population of 134,189.
Clifton is the smallest city in Greene County.
There are 20 cities in Greene County, Ohio.