East Dubuque is a city in Jo Daviess County, Illinois, United States. The population was 1,704 at the 2010 census, down from 1,995 at the 2000 census. East Dubuque is located alongside the Mississippi River. Across the river is the city of Dubuque, Iowa. About three miles north of the city is the Illinois - Wisconsin border. East Dubuque was originally known as Dunleith.