| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Cumberland | 1 | 6,006 | 6,372 | -0.99% | 157 | 38 | Township |
| Jefferson | 2 | 5,091 | 5,231 | -0.1% | 222 | 23 | Township |
| Jefferson | 3 | 3,914 | 3,726 | 0.8% | 117 | 34 | Township |
| Waynesburg | 4 | 3,550 | 3,990 | -2.23% | 4,410 | 1 | Borough |
| Jefferson | 5 | 2,431 | 2,387 | 0.25% | 153 | 16 | Township |
| Jefferson | 6 | 2,184 | 2,343 | -1.18% | 101 | 22 | Township |
| Dunkard | 7 | 2,023 | 2,168 | -1.17% | 64 | 32 | Township |
| Jefferson | 8 | 1,905 | 2,005 | -0.78% | 95 | 20 | Township |
| Jefferson | 9 | 1,842 | 1,919 | -0.59% | 75 | 25 | Township |
| Aleppo | 10 | 1,748 | 1,821 | -0.57% | 982 | 2 | Township |
| Jefferson | 11 | 1,398 | 1,437 | -0.36% | 34 | 41 | Township |
| Perry | 12 | 1,318 | 1,393 | -0.98% | 44 | 30 | Township |
| Jefferson | 13 | 1,110 | 1,117 | -0.18% | 49 | 23 | Township |
| Center | 14 | 1,057 | 1,115 | -0.75% | 22 | 49 | Township |
| Deemston | 15 | 732 | 750 | -0.41% | 76 | 10 | Borough |
| Richhill | 16 | 722 | 769 | -1.1% | 13 | 54 | Township |
| Jefferson | 17 | 657 | 656 | 0% | 1,084 | 1 | Borough |
| Whiteley | 18 | 542 | 567 | -0.73% | 17 | 32 | Township |
| Aleppo | 19 | 399 | 423 | -1.24% | 14 | 28 | Township |
| Carmichaels | 20 | 396 | 425 | -1.25% | 2,400 | 0 | Borough |
| Greene | 21 | 387 | 397 | -1.02% | 21 | 19 | Township |
| Rices Landing | 22 | 386 | 420 | -1.53% | 486 | 1 | Borough |
| Jefferson | 23 | 366 | 362 | 0.27% | 15 | 24 | Township |
| Springhill | 24 | 297 | 321 | -1.33% | 14 | 22 | Township |
| Greensboro | 25 | 244 | 266 | -1.61% | 2,259 | 0 | Borough |
| Jefferson | 26 | 236 | 254 | -1.26% | 1,255 | 0 | Borough |
| Gilmore | 27 | 221 | 237 | -0.9% | 10 | 23 | Township |
| Clarksville | 28 | 180 | 195 | -1.64% | 1,856 | 0 | Borough |
Cumberland is the largest city in Greene County, with a population of 6,006.
Clarksville is the smallest city in Greene County, with a population of 180.
There are 28 cities in Greene County, Pennsylvania.