Miamisburg is a city located in southern Montgomery County, Ohio, in the United States. It serves as a suburb of Dayton and is situated within the broader Dayton metropolitan area. According to the 2020 census, the city had a population of 19,923 residents.
The city was named in honor of the Miami people. Historically, Miamisburg is recognized for its industrial background, most notably for its involvement in nuclear operations during World War II.