12 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hillsboro | 1 | 2,645 | 2,728 | -0.53% | 1,084 | 2 | City |
| Marion | 2 | 1,874 | 1,921 | -0.43% | 679 | 3 | City |
| Peabody | 3 | 905 | 937 | -0.55% | 715 | 1 | City |
| Goessel | 4 | 549 | 557 | -0.18% | 1,449 | 0 | City |
| Florence | 5 | 376 | 390 | -0.53% | 491 | 1 | City |
| Burns | 6 | 229 | 235 | -0.43% | 666 | 0 | City |
| Lincolnville | 7 | 169 | 168 | 0% | 751 | 0 | City |
| Lehigh | 8 | 160 | 157 | 0.63% | 497 | 0 | City |
| Tampa | 9 | 104 | 107 | 0% | 584 | 0 | City |
| Durham | 10 | 88 | 88 | 0% | 506 | 0 | City |
| Ramona | 11 | 79 | 79 | 0% | 271 | 0 | City |
| Lost Springs | 12 | 56 | 55 | 0% | 252 | 0 | City |
Hillsboro is the largest city in Marion County, with a population of 2,645.
Lost Springs is the smallest city in Marion County, with a population of 56.
There are 12 cities in Marion County, Kansas.