Miamisburg is located in Montgomery county Ohio with a geographic area of 12.3 square miles. The total population in Miamisburg is 20,020 with 50.3% male and 49.7% female. Children under age 5 represent 6.5% of the population, under age 18 equal 25.4% of the population and over age 65 is 16.7% of the population. The median household income is $69,717, per capita income is $31,472. There are a total of 7,400 housing units with 71.0% owner occupied. Education includes 30.3% of residents that are high school graduates and 26.9% with a bachelor's degree or higher. The average temperature in Miamisburg in the summer is 73 degrees, and in the winter 32 degrees.