Ortonville
- County:
- Big Stone County
- County Seat:
- Yes
- Area (mi²):
- 4.193
- State:
- Minnesota
Ortonville is a city located in Big Stone County, Minnesota. Ortonville has a 2026 population of 1,970. It is also the county seat of Big Stone County. Ortonville is currently declining at a rate of -0.81% annually and its population has decreased by -2.48% since the most recent census, which recorded a population of 2,020 in 2020.