Middletown is a town in New Castle County, Delaware, United States. According to the 2010 Census, the population of the town is 18,871. According to the United States Census Bureau, the town has a total area of 6.4 square miles (17 sq/km), of which, 6.4 square miles (17 sq/km) of it is land and 0.16% is water. As of the census of 2000, there were 6,161 people, 2,298 households, and 1,631 families residing in the town. The population density was 962.4 people per square mile (371.7 sq/km). There were 2,514 housing units at an average density of 392.7 per square mile (151.7 sq/km). The racial makeup of the town was 94.42% White, 1.30% African American, 0.11% Native American, 0.78% Asian, 0.02% Pacific Islander, 1.93% from other races, and 1.44% from two or more races. Hispanic or Latino of any race were 5.29% of the population.