Harrisburg, OH has a population of 457 and is the 20,104th largest city in the United States. The population density is 2,965 per sq mi which is 1051% higher than the Ohio average and 3173% higher than the national average. The median age in Harrisburg is 40 which is approximately 1% higher than the Ohio average of 39. In Harrisburg, 58% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 81% of Harrisburg residents were born in Ohio, 19% were born out of state, 0% were born outside of the United States and 0% were foreign born.