Genesee County is a county in the U.S. state of Michigan. As of the 2020 Census, the population was 406,211, making it the fifth-most populous county in Michigan. The county seat and population center is Flint. Genesee County is considered to be a part of the greater Mid Michigan area. The county was named after Genesee County, New York, which in turn comes from the Seneca word Gen-nis'-hee-yo, meaning "Beautiful Valley". Genesee County comprises the Flint, MI Metropolitan Statistical Area.