20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Duchouquet | 1 | 14,421 | 14,678 | -0.19% | 342 | 42 | Township |
| St. Marys | 2 | 11,021 | 11,105 | -0.24% | 299 | 37 | Township |
| Wapakoneta | 3 | 9,782 | 9,955 | -0.36% | 1,490 | 7 | City |
| St. Marys | 4 | 8,369 | 8,401 | -0.08% | 1,793 | 5 | City |
| German | 5 | 3,730 | 3,751 | 0.48% | 202 | 18 | Township |
| Minster | 6 | 3,043 | 3,098 | -0.36% | 1,441 | 2 | Village |
| New Bremen | 7 | 3,015 | 3,040 | -0.17% | 1,289 | 2 | Village |
| Washington | 8 | 1,927 | 1,971 | -0.36% | 62 | 31 | Township |
| Noble | 9 | 1,830 | 1,866 | -0.44% | 60 | 31 | Township |
| Union | 10 | 1,707 | 1,743 | -0.35% | 48 | 36 | Township |
| Moulton | 11 | 1,621 | 1,646 | -0.49% | 58 | 28 | Township |
| Pusheta | 12 | 1,223 | 1,254 | -0.89% | 40 | 30 | Township |
| New Knoxville | 13 | 903 | 938 | -0.77% | 933 | 1 | Village |
| Clay | 14 | 766 | 785 | -0.26% | 25 | 30 | Township |
| Waynesfield | 15 | 737 | 754 | -0.54% | 1,108 | 1 | Village |
| Chippewa Park | 16 | 590 | 598 | -3.28% | 1,341 | 0 | CDP |
| New Hampshire | 17 | 518 | 556 | 4.65% | 849 | 1 | CDP |
| Uniopolis | 18 | 399 | 315 | 7.26% | 1,500 | 0 | CDP |
| St. Johns | 19 | 310 | 178 | 2.65% | 807 | 0 | CDP |
| Buckland | 20 | 225 | 237 | -1.32% | 750 | 0 | Village |
Duchouquet is the largest city in Auglaize County, with a population of 14,421.
Buckland is the smallest city in Auglaize County, with a population of 225.
There are 20 cities in Auglaize County, Ohio.