Dubuque County, Iowa

Dubuque County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 99,266, and was estimated to be 99,381 in 2025, making it the ninth-most populous county in Iowa. The county seat is Dubuque. The county is named for Julien Dubuque, the first European settler of Iowa. Dubuque County comprises the Dubuque, Iowa Metropolitan statistical area.