20 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Dubuque | 1 | 58,654 | 59,653 | -0.28% | 1,878 | 31 | City |
| Asbury | 2 | 6,099 | 5,954 | 0.4% | 1,919 | 3 | City |
| Dyersville | 3 | 4,588 | 4,500 | 0.33% | 660 | 7 | City |
| Cascade | 4 | 2,398 | 2,391 | 0.04% | 1,248 | 2 | City |
| Peosta | 5 | 2,326 | 1,933 | 2.92% | 822 | 3 | City |
| Epworth | 6 | 2,047 | 2,032 | 0.15% | 1,153 | 2 | City |
| Farley | 7 | 1,701 | 1,766 | -0.64% | 1,050 | 2 | City |
| New Vienna | 8 | 382 | 387 | -0.26% | 820 | 0 | City |
| Worthington | 9 | 371 | 380 | -0.27% | 821 | 0 | City |
| Holy Cross | 10 | 342 | 360 | -0.87% | 1,043 | 0 | City |
| Luxemburg | 11 | 238 | 244 | -0.42% | 504 | 0 | City |
| Rickardsville | 12 | 202 | 207 | -0.49% | 220 | 1 | City |
| Sherrill | 13 | 172 | 183 | -1.15% | 1,303 | 0 | City |
| Bernard | 14 | 117 | 116 | 0% | 1,258 | 0 | City |
| Centralia | 15 | 117 | 116 | 0% | 188 | 1 | City |
| Sageville | 16 | 102 | 107 | -0.97% | 121 | 1 | City |
| Zwingle | 17 | 86 | 86 | 0% | 528 | 0 | City |
| Graf | 18 | 76 | 75 | 0% | 571 | 0 | City |
| Bankston | 19 | 29 | 26 | 3.57% | 107 | 0 | City |
| Durango | 20 | 14 | 16 | 0% | 184 | 0 | City |
Dubuque is the largest city in Dubuque County, with a population of 58,654.
Durango is the smallest city in Dubuque County, with a population of 14.
There are 20 cities in Dubuque County, Iowa.