Randolph County is a county in the northern portion of the U.S. state of Missouri. As of the 2020 census, the population was 24,716. Its county seat is Huntsville. The county was organized January 22, 1829, and named for U.S. Representative and U.S. Senator John Randolph of Roanoke, Virginia.

Huntsville is a city in Randolph County, Missouri, United States. The population was 1,376 at the 2020 census. It is the county seat of Randolph County.