Bettendorf is a city in Scott County, Iowa, United States. Bettendorf is the fifteenth largest city in the U.S. state of Iowa and the fourth largest city in the "Quad Cities". It is part of the Davenport-Moline-Rock Island, IA-IL Metropolitan Statistical Area. The population was 33,217 at the 2010 census, and was estimated to be 34,707 by July 2013. Bettendorf is one of the Quad Cities, along with neighboring Davenport and the Illinois cities of Moline, East Moline and Rock Island.