Diamondhead is a city in southeastern Hancock County, Mississippi, United States. The city is located just over 50 miles (80 km) northeast of New Orleans, Louisiana. It is part of the Gulfport−Biloxi Metropolitan Statistical Area. In February 2012, Diamondhead was officially incorporated as a city. At the time of the 2010 census, when Diamondhead was an unincorporated census-designated place, the population was 8,425. The city population, with slightly different boundaries, was estimated at 8,217 in 2016.
Unlike most of the Mississippi Gulf Coast, which is relatively level, the Diamondhead area has more rolling topography, with elevations ranging from sea level to over 100 feet (30 m). The city is bordered to the south by the Bay of Saint Louis. Rotten Bayou runs west and northwest of the city. Harrison County borders Diamondhead to the east.
According to the United States Census Bureau, in 2010 the Diamondhead CDP had a total area of 11.7 square miles (30.3 km), of which 11.1 square miles (28.7 km) were land and 0.58 square miles (1.5 km), or 5.04%, were water.
As of the 2010 census, there were 8,425 people, 3,586 households, and 2,507 families residing in the CDP. The population density was 745.6 people per square mile (286.6/km). There were 4,308 housing units at an average density of 381.2/sq mi (146.5/km). The racial makeup of the CDP was 93.9% White, 2.9% African American, 0.4% Native American, 1.1% Asian, 0.1% Pacific Islander, 0.3% from other races, and 1.2% from two or more races. Hispanic or Latino of any race were 3.3% of the population.
There were 3,586 households out of which 23.8% had children under the age of 18 living with them, 59.3% were married couples living together, 7.4% had a female householder with no husband present, and 30.1% were non-families. 25.9% of all households were made up of individuals and 12.2% had someone living alone who was 65 years of age or older. The average household size was 2.31 and the average family size was 2.77.
In the CDP the population was spread out with 21.1% under the age of 18, 3.6% from 18 to 24, 20.7% from 25 to 44, 28.9% from 45 to 64, and 25.7% who were 65 years of age or older. The median age was 48 years. For every 100 females, there were 93.9 males. Females made up 52% of the population.
The median income for a household in the CDP was $51,361, and the median income for a family was $58,533. Males had a median income of $41,725 versus $29,595 for females. The per capita income for the CDP was $26,631. About 4.3% of families and 7.2% of the population were below the poverty line, including 10.7% of those under age 18 and 2.7% of those age 65 or over.