5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Oconto | 1 | 4,642 | 4,619 | 0.09% | 685 | 7 | City |
| Oconto Falls | 2 | 3,036 | 2,973 | 0.4% | 1,055 | 3 | City |
| Gillett | 3 | 1,268 | 1,291 | -0.39% | 939 | 1 | City |
| Lena | 4 | 539 | 533 | 0.19% | 507 | 1 | Village |
| Suring | 5 | 518 | 521 | -0.19% | 505 | 1 | Village |
Oconto is the largest city in Oconto County, with a population of 4,642.
Suring is the smallest city in Oconto County, with a population of 518.
There are 5 cities in Oconto County, Wisconsin.