Wyandotte County is a county in the U.S. state of Kansas. Its county seat and most populous city is Kansas City, with which it shares a unified government. As of the 2020 census, the population was 169,245, making it Kansas's fourth-most populous county. The county was named after the Wyandot tribe.

Kansas City is the third-most populous city in the U.S. state of Kansas, and the county seat of Wyandotte County. It is an inner suburb of the older and more populous Kansas City, Missouri, after which it is named. As of the 2020 census, the population of the city was 156,607, making it one of four principal cities in the Kansas City metropolitan area. It is situated at Kaw Point, the junction of the Missouri and Kansas rivers. It is part of a consolidated city-county government known as the "Unified Government". It is the location of the University of Kansas Medical Center and Kansas City Kansas Community College.