Dearborn is a city in Wayne County in the U.S. state of Michigan. At the 2020 census, it had …Dearborn is a city in Wayne County in the U.S. state of Michigan. At the 2020 census, it had a population of 109,976. Dearborn is the seventh most-populated city in Michigan and is home to the largest Muslim population in the United States per capita. It also is home to the largest mosque in the United States.