Romulus, MI has a population of 23,457 and is the 1,857th largest city in the United States. The population density is 659 per sq mi which is 270% higher than the Michigan average and 627% higher than the national average. The median age in Romulus is 37 which is approximately 7% lower than the Michigan average of 40. In Romulus, 48% of the population over 15 years of age are married, 94% speak English and 2% speak Spanish. 79% of Romulus residents were born in Michigan, 16% were born out of state, 0% were born outside of the United States and 5% were foreign born.