Ankeny (, ) is a city in Polk County, Iowa, United States and a suburb of the state capital of Des Moines, as part of the Des Moines-West Des …Ankeny (, ) is a city in Polk County, Iowa, United States and a suburb of the state capital of Des Moines, as part of the Des Moines-West Des Moines, IA metropolitan statistical area. As of the 2020 census, the population of Ankeny was 67,887, making it the seventh most populous city in the state. It is one of the fastest-growing cities in Iowa. Currently, the city's incorporated area totals 29.14 square miles.