Adams County is a county in the U.S. state of Iowa. As of the 2020 census, the population was 3,704, making it Iowa's least-populous county. Its county seat is Corning.

Corning is a city in Quincy Township, Adams County, Iowa, United States. The population was 1,564 at the 2020 census. It is the county seat of Adams County. Corning is located just north of the intersection of U.S. Route 34 and Iowa Highway 148. Corning is perhaps best known as the birthplace of Johnny Carson. Daniel Webster Turner, who was governor of Iowa from 1931 to 1933, was born in Corning on March 17, 1877.