As of the census of 2000, there were 22,121 people, 8,021 households, and 6,007 families residing in the county. The population density was 42 people per square mile (16/km²). There were 8,889 housing units at an average density of 17 per square mile (6/km²). The racial makeup of the county was 62.57% White, 34.37% Black or African American, 0.78% Native American, 0.36% Asian, 0.03% Pacific Islander, 0.52% from other races, and 1.37% from two or more races. 1.33% of the population were Hispanic or Latino of any race.
There were 8,021 households out of which 31.70% had children under the age of 18 living with them, 56.30% were married couples living together, 13.20% had a female householder with no husband present, and 25.10% were non-families. 20.50% of all households were made up of individuals and 8.20% had someone living alone who was 65 years of age or older. The average household size was 2.69 and the average family size was 3.08.
In the county, the population was spread out with 24.80% under the age of 18, 7.40% from 18 to 24, 29.90% from 25 to 44, 25.00% from 45 to 64, and 12.90% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 99.10 males. For every 100 females age 18 and over, there were 97.50 males.
The median income for a household in the county was $39,845, and the median income for a family was $43,533. Males had a median income of $31,701 versus $22,455 for females. The per capita income for the county was $18,342. About 7.20% of families and 9.40% of the population were below the poverty line, including 12.00% of those under age 18 and 11.70% of those age 65 or over.
Economic growth in Caroline in the last five years have been rapid, mostly due to affordable housing and close proximity to Northern Virginia and Washington D.C. In 2005, Caroline was recognized as the 10th Fastest Growing County in America. Also in 2005, Caroline County won the Virginia Community Economic Development Award (CEDA) for Business Recruitment and the CEDA Award for the entire south from the Southern Economic Development Council.
Among recent Economic Development successes in Caroline have been the recruitment of the State Fair of Virginia, to open in 2009 (previously in Richmond since 1854 when the first State Fair opened in Monroe Park), Remuda Programs for Eating Disorders, The Virginia Sports Complex, and the multi-national electronics firm, M.C. Dean.