Davison County is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 19,956, making it the 10th most populous county in South Dakota. Its county seat is Mitchell. The county was created in 1873 and organized in 1874. It was named for Henry C. Davison, the first settler in the county.

Mitchell is a city in and the county seat of Davison County, South Dakota, United States. The population was 15,660 at the 2020 census making it the sixth most populous city in South Dakota.