As of the census of 2000, there were 20,047 people, 7,855 households, and 5,317 families residing in the county. The population density was 41 people per square mile (16/km2). There were 8,793 housing units at an average density of 18 per square mile (7/km2). The racial makeup of the county was 71.76% White, 26.23% Black or African American, 0.25% Native American, 0.27% Asian, 0.01% Pacific Islander, 0.62% from other races, and 0.85% from two or more races. Approximately 1.57% of the population were Hispanic or Latino of any race. Among the major first ancestries reported in Pemiscot County were 31.9% American, 7.8% Irish, 5.6% English, and 5.5% German ancestry.