6 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rock Springs | 1 | 22,835 | 23,495 | -0.57% | 1,156 | 20 | City |
| Green River | 2 | 11,390 | 11,808 | -0.73% | 825 | 14 | City |
| Wamsutter | 3 | 195 | 202 | -1.02% | 120 | 2 | Town |
| Superior | 4 | 181 | 188 | -1.09% | 162 | 1 | Town |
| Granger | 5 | 97 | 96 | 0% | 37 | 3 | Town |
| Bairoil | 6 | 65 | 68 | -1.52% | 46 | 1 | Town |
Rock Springs is the largest city in Sweetwater County, with a population of 22,835.
Bairoil is the smallest city in Sweetwater County, with a population of 65.
There are 6 cities in Sweetwater County, Wyoming.