Ainsworth is a city in Washington County, Iowa, United States. It part of the Iowa City, Iowa Metropolitan Statistical Area. The population was 524 at the 2000 census. It is part of the Highland Community School District.
Ainsworth is located at 41°17′25″N 91°33′15″W / 41.29028°N 91.55417°W / 41.29028; -91.55417 (41.290175, -91.554283).
According to the United States Census Bureau, the city has a total area of 0.4 square miles (1.0 km²), all of it land.