Bettendorf is a city in Scott County, Iowa, United States. The population was 39,102 at the 2020 census. Bettendorf is one of the five cities that comprise the Quad Cities region along the Mississippi River. It is located adjacent to Davenport, Iowa, and across the river from Moline, East Moline, and Rock Island in Illinois. The Quad Cities metropolitan area had a population of 384,324 as of the 2020 census.