Walnut is a city in Pottawattamie County, Iowa, United States. The population was 747 at the time of the 2020 census. Walnut is located on Interstate 80 and is famous for its many antique stores. In recent years Walnut has become a regional center of wind turbine electrical generation.
thumb|upright|Wind turbine near Walnut.
History
Walnut was incorporated as a city in 1877.
Geography
According to the United States Census Bureau, the city has a total area of , all land.