Saline County is located along the Missouri River in the U.S. state of Missouri. As of the 2020 census, the population was 23,333. Its county seat is Marshall. The county was established November 25, 1820, and named for the region's salt springs.

Marshall is a city in Saline County, Missouri, United States. The population was 13,065 at the 2010 census. It is the county seat of Saline County. The Marshall Micropolitan Statistical Area consists of Saline County. It is home to Missouri Valley College.